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Reproductive Tissues (reproductive + tissue)
Selected AbstractsINDEPENDENT EVOLUTION OF COMPLEX LIFE HISTORY ADAPTATIONS IN TWO FAMILIES OF FISHES, LIVE-BEARING HALFBEAKS (ZENARCHOPTERIDAE, BELONIFORMES) AND POECILIIDAE (CYPRINODONTIFORMES)EVOLUTION, Issue 11 2007David Reznick We have previously documented multiple, independent origins of placentas in the fish family Poeciliidae. Here we summarize similar analyses of fishes in the family Zenarchopteridae. This family includes three live-bearing genera. Earlier studies documented the presence of superfetation, or the ability to carry multiple litters of young in different stages of development in the same ovary, in some species in all three genera. There is also one earlier report of matrotrophy, or extensive postfertilization maternal provisioning, in two of these genera. We present detailed life-history data for approximately half of the species in all three genera and combine them with the best available phylogeny to make inferences about the pattern of life-history evolution within this family. Three species of Hemirhamphodon have superfetation but lack matrotrophy. Most species in Nomorhamphus and Dermogenys either lack superfetation and matrotrophy or have both superfetation and matrotrophy. Our phylogenetic analysis shows that matrotrophy may have evolved independently in each genus. In Dermogenys, matrotrophic species produce fewer, larger offspring than nonmatrotrophic species. In Nomorhamphus; matrotrophic species instead produce more and smaller offspring than lecithotrophic species. However, the matrotrophic species in both genera have significantly smaller masses of reproductive tissue relative to their body sizes. All aspects of these results are duplicated in the fish family Poeciliidae. We discuss the possible adaptive significance of matrotrophy in the light of these new results. The two families together present a remarkable opportunity to study the evolution of a complex trait because they contain multiple, independent origins of the trait that often include close relatives that vary in either the presence or absence of the matrotrophy or in the degree to which matrotrophy is developed. These are the raw materials that are required for either an analysis of the adaptive significance of the trait or for studies of the genetic mechanisms that underlie the evolution of the trait. [source] Plant profilin isovariants are distinctly regulated in vegetative and reproductive tissuesCYTOSKELETON, Issue 1 2002Muthugapatti K. Kandasamy Abstract Profilin is a low-molecular weight, actin monomer-binding protein that regulates the organization of actin cytoskeleton in eukaryotes, including higher plants. Unlike the simple human or yeast systems, the model plant Arabidopsis has an ancient and highly divergent multi-gene family encoding five distinct profilin isovariants. Here we compare and characterize the regulation of these profilins in different organs and during microspore development using isovariant-specific monoclonal antibodies. We show that PRF1, PRF2, and PRF3 are constitutive, being strongly expressed in all vegetative tissues at various stages of development. These profilin isovariants are also predominant in ovules and microspores at the early stages of microsporogenesis. In contrast, PRF4 and PRF5 are late pollen-specific and are not detectable in other cell types of the plant body including microspores and root hairs. Immunocytochemical studies at the subcellular level reveal that both the constitutive and pollen-specific profilins are abundant in the cytoplasm. In vegetative cell types, such as root apical cells, profilins showed localization to nuclei in addition to the cytoplasmic staining. The functional diversity of profilin isovariants is discussed in light of their spatio-temporal regulation during vegetative development, pollen maturation, and pollen tube growth. Cell Motil. Cytoskeleton 52:22,32, 2002. © 2002 Wiley-Liss, Inc. [source] Fathers, fruits and photosynthesis: pollen donor effects on fruit photosynthesis in wild parsnipECOLOGY LETTERS, Issue 11 2003Arthur R. Zangerl Abstract Chlorophyll is frequently present in plant reproductive tissues and indicates that photosynthesis is occurring in these parts. Photosynthesis by a reproductive organ can contribute as much as 65% to its own growth. Given the advantages that increased photosynthetic rates might have on development of individual seeds competing for resources, selection can be expected to favour the ability of offspring to influence photosynthetic rates of the tissues surrounding them. We report in this study the first evidence that the pollen genotype can influence the rate of photosynthesis in the fruit tissues surrounding the developing offspring. Using a novel chlorophyll fluorescence imaging instrument to quantify quantum efficiency of photosystem II, we found significant differences in photosynthetic rates among fruits in wild parsnip, Pastinaca sativa L, associated with different pollen genotypes. [source] DNA adduct kinetics in reproductive tissues of DNA repair proficient and deficient male mice after oral exposure to benzo(a)pyreneENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 2 2010Nicole Verhofstad Abstract Benzo(a)pyrene (B[a]P) can induce somatic mutations, whereas its potential to induce germ cell mutations is unclear. There is circumstantial evidence that paternal exposure to B[a]P can result in germ cell mutations. Since DNA adducts are thought to be a prerequisite for B[a]P induced mutations, we studied DNA adduct kinetics by 32P-postlabeling in sperm, testes and lung tissues of male mice after a single exposure to B[a]P (13 mg/kg bw, by gavage). To investigate DNA adduct formation at different stages of spermatogenesis, mice were sacrificed at Day 1, 4, 7, 10, 14, 21, 32, and 42 after exposure. In addition, DNA repair deficient (Xpc,/,) mice were used to study the contribution of nucleotide excision repair in DNA damage removal. DNA adducts were detectable with highest levels in lung followed by sperm and testis. Maximum adduct levels in the lung and testis were observed at Day 1 after exposure, while adduct levels in sperm reached maximum levels at ,1 week after exposure. Lung tissue and testis of Xpc,/, mice contained significantly higher DNA adduct levels compared to wild type (Wt) mice over the entire 42 day observation period (P < 0.05). Differences in adduct half-life between Xpc,/, and Wt mice were only observed in testis. In sperm, DNA adduct levels were significantly higher in Xpc,/, mice than in Wt mice only at Day 42 after exposure (P = 0.01). These results indicate that spermatogonia and testes are susceptible for the induction of DNA damage and rely on nucleotide excision repair for maintaining their genetic integrity. Environ. Mol. Mutagen. 2010. © 2009 Wiley-Liss, Inc. [source] Epigenetic regulation and downstream targets of the Rhox5 homeobox geneINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2008S. Shanker Summary The discovery of the Rhox homeobox gene cluster on the X chromosome opens up new vistas in the regulation of reproductive processes in mammals. In mice, this cluster comprises more than 30 genes that are selectively expressed in reproductive tissues. A subset of Rhox genes are androgen and AR regulated in postnatal and adult Sertoli cells, making them candidates to mediate androgen-dependent steps during spermatogenesis. The best characterized of these androgen/AR-regulated genes is Rhox5 (Pem), the founding member of the Rhox gene cluster. Targeted deletion of Rhox5 in mice causes male subfertility marked by increased germ-cell apoptosis and decreased sperm count and motility. Microarray analyses identified a wide variety of genes regulated by Rhox5 in Sertoli cells. One of them is the tumour suppressor UNC5C, a pro-apoptotic molecule previously only known to be involved in brain development. Targeted deletion of Unc5c causes decreased germ-cell apoptosis in postnatal and adult testes, indicating that it also has a role in spermatogenesis and supporting a model in which Rhox5 promotes germ-cell survival by downregulating Unc5c. Rhox5 has two independently regulated promoters that have distinct expression patterns. The unique tissue-specific and developmentally regulated transcription pattern of these two promoters appear to be controlled by DNA methylation. Both promoters are methylated in tissues in which they are not expressed, suggesting that DNA methylation serves to repress Rhox5 expression in inappropriate cell types and tissues. In summary, the Rhox gene cluster is an epigenetically regulated set of genes encoding a large number of transcription factors that are strong candidates to regulate gametogenesis and other aspects of reproduction. [source] Metals in human placenta: focus on the effects of cadmium on steroid hormones and leptin,JOURNAL OF APPLIED TOXICOLOGY, Issue 3 2010Sandra Stasenko Abstract Cadmium and other metallic ions can act as metalloestrogens and endocrine disruptors of reproductive tissues and fetal development in mammals, including humans. The detrimental effects occur with respect to the synthesis of both steroid and polypeptide hormones in the placenta. Leptin is produced by the trophoblast and may regulate fetal organogenesis and development. In human term placentas, concentrations of toxic metals and their effects on steroidogenesis were assessed in healthy parturients (109 non-smokers and 99 smokers) in relation to tobacco smoking. Trace elements (cadmium, lead, iron, zinc and copper) were analyzed in placentas using atomic absorption spectroscopy, and steroid hormones (progesterone and estradiol) were assayed in placental samples by an enzyme-immunometric method. Cadmium concentrations were doubled in placentas of smokers as compared with non-smokers, and placental lead and zinc concentrations increased significantly. Placental concentrations of iron, copper, progesterone and estradiol did not differ. In addition, human trophoblast cells were co-cultured with 0, 5, 10 or 20,,µm CdCl2 for 96,,h and leptin mRNA assessed by quantitative polymerase chain reaction. Leptin mRNA declined dose-responsively as a result of CdCl2 exposure. Collectively, the results confirm that human placental tissue offers a unique opportunity to biomonitor cadmium exposure in both the maternal and the internal fetal environments. In addition, the results strongly suggest that cadmium may cause a decline in placental leptin synthesis, as we have previously shown for placental progesterone production. This may constitute further evidence of the endocrine-disrupting effects of cadmium, as a constituent of tobacco smoke, on reproduction in women. Copyright © 2009 John Wiley & Sons, Ltd. [source] Effect of textile waste water on the spermatogenesis of male albino ratsJOURNAL OF APPLIED TOXICOLOGY, Issue 3 2003R. S. Gupta Abstract Textile waste water released from dyeing and printing industries situated in Sanganer, Jaipur (India), brought about inhibition of spermatogenesis in male rats. Water analysis showed the presence of heavy metals at more than permissible limits. Oral administration of waste water to the rats at the dose level of 26.6 ml kg,1 body wt. significantly reduced the weights of testes, epididymides and seminal vesicle. Treated animals showed a notable depression of various stages of spermatogenesis. The production of spermatids was inhibited by 70.8% in waste-water-treated rats. The populations of spermatogonia, preleptotene spermatocytes and secondary spermatocytes were decreased by 67.2, 71.1 and 73.2%, respectively. The total number of Sertoli cells was affected after waste water treatment. Reduced sperm count and motility resulted in treated groups. A significant fall in the content of various biochemical parameters of reproductive tissues was observed after water treatment. Copyright © 2003 John Wiley & Sons, Ltd. [source] Argemone oil induced cellular damage in the reproductive tissues of transgenic Drosophila melanogaster: Protective role of 70 kDa heat shock proteinJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 4 2003Indranil Mukhopadhyay Abstract We explored the reproductive toxicity of argemone oil and its principal alkaloid fraction in transgenic Drosophila melanogaster (hsp70-lacZ) Bg9. The toxicity of argemone oil has been attributed to two of its physiologically active benzophenanthridine alkaloids, sanguinarine and dihydrosanguinarine. Freshly eclosed first instar larvae of transgenic Drosophila melanogaster were transferred to different concentrations of argemone oil and its alkaloid fraction contaminated food. Virgin flies that eclosed from the contaminated food were pair-mated to look into the effect on reproduction. The study was further extended by investigating hsp70 expression and tissue damage in larval gonads, genital discs, and reproductive organs of adult fly. Our results showed that argemone oil was more cytotoxic than its principal alkaloid fraction. Moreover, it was the male fly that was more affected compared to its opposite number. The accessory glands of male reproductive system of the fly, which did not express hsp70, exhibited severe damage as evidenced by Trypan blue staining. This prompted us to explore the ultrastructural morphology of the gland, which showed acute signs of necrosis in both the cell types as evident by necrotic nuclei, higher vacuolization, and disorganized endoplasmic reticulum, decrease in the number of Golgi vesicles and disorganized, loosely packed filamentous structures in the lumen of the accessory gland, at the higher concentrations of the adulterant. The study showed the reproductive toxicity of argemone oil and its alkaloid fraction in transgenic Drosophila melanogaster and further confirmed the cytoprotective role of hsp70. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:223,234, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10082. [source] Long-Term Sensitivity of Uterus and Hypothalamus/Pituitary Axis to 17,-Estradiol Is Higher Than That of Bone in Rats,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 11 2004Reinhold G Erben MD Abstract We examined the long-term sensitivity of uterus and bone to low-dose 17,-estradiol in a 4-month experiment in OVX rats and found that a dose of estradiol that fully protected against uterine atrophy did not protect against bone loss. Our results suggest higher estrogen sensitivity of the uterus compared with bone. Introduction: Estrogen is essential for the function of reproductive tissues and for the normal acquisition and maintenance of bone mass in females. This study was designed to examine the long-term sensitivity of the uterus and bone to low-dose estrogen. Materials and Methods: In preliminary experiments, we determined the lowest subcutaneous dose of 17,-estradiol able to fully protect against uterine atrophy in ovariectomized (OVX) rats. This dose was found to be 1.5 ,g/kg, given five times per week. Subsequently, groups of sham-operated (SHAM) or OVX 6-month-old rats (n = 8 each) were subcutaneously injected with vehicle or 1.5 ,g/kg 17,-estradiol five times per week. All animals were killed 4 months after surgery. Serum osteocalcin and urinary deoxypyridinoline were measured as biochemical markers of bone turnover. Bones were analyzed by bone histomorphometry and pQCT. Results and Conclusions: Our study clearly showed that a dose of estradiol that restores physiological estradiol serum levels, fully maintains uterine weight in OVX rats at the SHAM control level, and suppresses serum follicle-stimulating hormone (FSH) by 67% relative to OVX vehicle controls does not provide significant protection against OVX-induced bone loss at different cancellous and cortical bone sites. We conclude that the long-term sensitivity of the uterus and the hypothalamus/pituitary axis to 17,-estradiol is higher than that of bone in rats. [source] Gene Expression Profiles of Intracellular and Membrane Progesterone Receptor Isoforms in the Mediobasal Hypothalamus During Pro-OestrusJOURNAL OF NEUROENDOCRINOLOGY, Issue 12 2009B. Liu Progesterone action is mediated by its binding to specific receptors. Two progesterone receptor (PR) isoforms (PRA and PRB), three membrane progesterone receptor (mPR) subtypes (mPR,, mPR, and mPR,) and at least one progesterone membrane-binding protein [PR membrane component 1 (PRmc1)] have been identified in reproductive tissues and brain of various species. In the present study, we examined gene expression patterns for PR isoforms, mPR subtypes and PRmc1 in the rat mediobasal hypothalamus (MBH) during pro-oestrus. The mRNA level for each receptor subtype was quantified by a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) at the time points: 13.00 h on dioestrous day 2; 09.00, 13.00, 17.00 and 22.00 h on pro-oestrus; and 13.00 h on oestrus. For PR, one primer set amplified PRA+PRB, whereas a second primer set amplified PRB. As expected, PRA+PRB mRNA expression was greater than PRB in MBH tissue. PRB mRNA levels increased throughout the day on pro-oestrus, with the highest levels being observed at 17.00 h. PRB mRNA levels in the MBH were increased by 2.4- and 3.0-fold at 13.00 and 17.00 h, respectively, on pro-oestrus compared to 13.00 h on dioestrous day 2. There were differential mRNA expression levels for mPRs and PRmc1 in the MBH, with the highest expression for PRmc1 and the lowest for mPR,. The mPR, mRNA contents at 13.00 and 17.00 h on pro-oestrus were increased by 1.5-fold compared to that at 13.00 h on dioestrous day 2. The mPR, mRNA levels at 13.00 and 17.00 h on pro-oestrus were 2.5- and 2.4-fold higher compared to that at 13.00 h on dioestrous day 2, respectively. PRA+PRB, mPR, and PRmc1 mRNA levels did not vary on pro-oestrus. These findings suggest that the higher expression of PRB, mPR, and mPR, in the MBH on pro-oestrous afternoon may influence both genomic and nongenomic mechanisms of progesterone action during the critical pre-ovulatory period. [source] Neuroendocrinological and Molecular Aspects of Insect ReproductionJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2004G. Simonet Abstract This review summarizes recent advances and novel concepts in the area of insect reproductive neuroendocrinology. The role of ,classic' hormones, such as ecdysteroids and juvenoids, to control reproduction is well documented in a large variety of insect species. In adult gonads, ecdysteroids appear to induce a cascade of transcription factors, many of which also occur during the larval molting response. Recent molecular and functional data have created opportunities to study an additional level of regulation, that of neuropeptides, growth factors and their respective receptors. As a result, many homologs of factors playing a role in vertebrate reproductive physiology have been discovered in insects. This review highlights several neuropeptides controlling the biosynthesis and release of the ,classic' insect hormones, as well as various peptides and biogenic amines that regulate behavioural aspects of the reproduction process. In addition, hormone metabolizing enzymes and second messenger pathways are discussed with respect to their role in reproductive tissues. Finally, we speculate on future prospects for insect neuroendocrinological research as a consequence of the recent ,Genomics Revolution'. [source] Complement 3 deficiency impairs early pregnancy in miceMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 7 2009Wang-Ngai Chow Human oviductal cells produce complement-3 (C3) and its derivative, iC3b. These molecules are important in immune responses. Our recent study suggested that iC3b also possessed embryotrophic activity and it stimulates the blastulation and hatching rates of in vitro cultured mouse embryos. The objective is to study the impact of C3 deficiency on early pregnancy in vivo using homozygous C3-deficient (C3KO) and wild-type (C3WT) mice. C3 protein was undetectable in the reproductive tissues of C3KO mice. Deficiency in C3 is associated with significantly longer estrous cycle (P,=,0.037). No significant difference was found in the ovulation rate, total cell count in blastocysts and implantation rate between the wild-type and the C3KO mice, though C3KO mice tended to have lower values in the latter two parameters. On day 15 of pregnancy, C3KO mice had fewer conceptus (P,<,0.001) and higher resorption rate (P,<,0.001) than that of C3WT mice. The fetal and placental weights (P,<,0.001) were lower in the C3KO mice. The placenta of C3KO mice had smaller spongiotrophoblast (P,=,0.001) and labyrinth (P,=,0.037). Deficiency in C3 is associated with mild impairment in early pregnancy including longer estrous cycle and higher resorption rates after implantation. The impairment may be related to compromised placental development leading to under-developed fetuses. Mol. Reprod. Dev. 76: 647,655, 2009. © 2009 Wiley-Liss, Inc. [source] NSSR1 is regulated in testes development and cryptorchidism and promotes the exon 5-included splicing of CREB transcriptsMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2007Ping-Jie Xiao Abstract Neural salient serine/arginine rich protein 1 (NSSR1, alternatively SRp38) is a newly identified splicing factor that is highly expressed in neural and reproductive tissues. We showed that the expression of testicular NSSR1 increased significantly during mouse testes development. NSSR1 was mainly expressed in germ cells, but barely detected in Sertoli cells. Testicular NSSR1 was mostly phosphorylated and cytosolic in germ cells. In comparison, pituitary NSSR1 was mostly dephosphorylated and nuclear. In the cryptorchid testes, the dephosphorylated NSSR1 was significantly increased. RT-PCR analysis demonstrated that the alternative splicing of CREB and CREM genes was altered in the cryptorchid testes. In addition, CREB transcripts were associated with NSSR1 either in testes tissues or cultured GC-1 cells. Moreover, the studies with NSSR1 over-expression or silence demonstrated that NSSR1 promoted the exon 5 inclusion of CREB, indicating that NSSR1 is a new factor that regulates the alternative exon 5 inclusion of CREB transcripts. The findings for the first time provide the evidence indicating the potential importance of NSSR1 in testes development, spermatogenesis and cryptorchidism. Mol. Reprod. Dev. 74: 1363,1372, 2007. © 2007 Wiley-Liss, Inc. [source] Seasonal fluctuations of selenium and sulfur accumulation in selenium hyperaccumulators and related nonaccumulatorsNEW PHYTOLOGIST, Issue 3 2007Miriam L. Galeas Summary ,,Some plants hyperaccumulate selenium (Se) up to 1% of dry weight. This study was performed to obtain insight into whole-plant Se fluxes in hyperaccumulators. ,,Selenium hyperaccumulators Astragalus bisulcatus and Stanleya pinnata were monitored over two growing seasons for seasonal fluctuations in concentrations of Se and the chemically similar element sulfur (S). The related nonhyperaccumulators Astragalus sericoleucus, Oxytropis sericea and Thlaspi montanum were included for comparison. ,,In both hyperaccumulators leaf Se decreased from April to October, coinciding with Se hyperaccumulation in flowers and seeds. Root Se levels were lowest in summer. Selenium concentration decreased with leaf age in both hyperaccumulators. Leaf S levels peaked in summer in all plant species, as did Se levels in nonhyperaccumulators. Selenium and S levels tended to be negatively correlated in hyperaccumulators, and positively correlated in nonhyperaccumulators. ,,These results suggest a specific flow of Se in hyperaccumulator plants over the growing season, from root to young leaves in spring, followed by remobilization from aging leaves to reproductive tissues in summer, and back to roots in the autumn. [source] Altered expression of cytokines and sex steroid receptors in the reproductive tract of cysticercotic male micePARASITE IMMUNOLOGY, Issue 2 2010M. RODRÍGUEZ-DORANTES Summary Infection with Taenia crassiceps cysticerci in male mice produces an increase in serum oestradiol levels, whereas serum testosterone is abolished. Concomitantly, complete atrophy of the reproductive tract of infected male mice is observed. The present study was undertaken to determine the expression pattern of cytokines involved in steroidogenesis and sex steroid receptors in the reproductive tissues of normal and infected male mice, and relating this expression pattern to whole parasite counts, serum sex steroid levels and pathology of the reproductive tract in infected male mice. The expression of IL-4, IFN-, and TNF-, in testes and seminal vesicles was markedly increased in infected mice; however, IL-10 and IL-1, expression was importantly decreased in the same organs. IL-2 expression in reproductive tissues was not affected by infection. The infection markedly induced the expression of androgen receptor, in both reproductive organs tested, while subtypes of oestrogen receptors were decreased in both tissues. [source] The function of SULTR2;1 sulfate transporter during seed development in Arabidopsis thalianaPHYSIOLOGIA PLANTARUM, Issue 1 2005Motoko Awazuhara SULTR2;1 is a low-affinity sulfate transporter expressed in the vascular tissues of roots and leaves for interorgan transport of sulfate in Arabidopsis thaliana. Transgenic Arabidopsis carrying a fusion gene construct of SULTR2;1 5,-promoter region and ,-glucuronidase coding sequence (GUS) demonstrated that within the reproductive tissues, SULTR2;1 is specifically expressed in the bases and veins of siliques and in the funiculus, which connects the seeds and the silique. The antisense suppression of SULTR2;1 mRNA caused decrease of sulfate contents in seeds and of thiol contents both in seeds and leaves, as compared with the wildtype (WT). The effect of antisense suppression of SULTR2;1 on seed sulfur status was determined by introducing a sulfur-indicator construct, p35S::,SRx3:GUS, which drives the expression of GUS reporter under a chimeric cauliflower mosaic virus 35S promoter containing a triplicate repeat of sulfur-responsive promoter region of soybean ,-conglycinin , subunit (,SRx3). The mature seeds of F1 plants carrying both the SULTR2;1 antisense and p35S::,SRx3:GUS constructs exhibited significant accumulation of GUS activities on sulfur deficiency, as compared with those carrying only the p35S::,SRx3:GUS construct in the WT background. These results suggested that SULTR2;1 is involved in controlling translocation of sulfate into developing siliques and may modulate the sulfur status of seeds in A. thaliana. [source] Expression of CP4 EPSPS in microspores and tapetum cells of cotton (Gossypium hirsutum) is critical for male reproductive development in response to late-stage glyphosate applicationsPLANT BIOTECHNOLOGY JOURNAL, Issue 5 2006Yun-Chia Sophia Chen Summary Plants expressing Agrobacterium sp. strain CP4 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) are known to be resistant to glyphosate, a potent herbicide that inhibits the activity of the endogenous plant EPSPS. The RR1445 transgenic cotton line (current commercial line for Roundup Ready® Cotton) was generated using the figwort mosaic virus (FMV) 35S promoter to drive the expression of the CP4 EPSPS gene, and has excellent vegetative tolerance to glyphosate. However, with high glyphosate application rates at developmental stages later than the four-leaf stage (late-stage applications: applications that are inconsistent with the Roundup® labels), RR1445 shows male sterility. Another transgenic cotton line, RR60, was generated using the FMV 35S promoter and the Arabidopsis elongation factor-1, promoter (AtEF1,) for the expression of CP4 EPSPS. RR60 has excellent vegetative and reproductive tolerance to applications of glyphosate at all developmental stages. Histochemical analyses were conducted to examine the male reproductive development at the cellular level of these cotton lines in response to glyphosate applications, and to investigate the correlation between glyphosate injury and the expression of CP4 EPSPS in male reproductive tissues. The expression of CP4 EPSPS in RR60 was found to be strong in all male reproductive cell types. Conversely, CP4 EPSPS expression in RR1445 was low in pollen mother cells, male gametophytes and tapetum, three crucial male reproductive cell types. Our results indicate that the FMV 35S promoter, although expressing strongly in most vegetative tissues in plants, has extremely low activity in these cell types. [source] The Peritoneal Mesothelium Covering the Genital Tract and its Ligaments in the Female Pig Shows Signs of Active FunctionTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 7 2007Jesús Luis Yániz Abstract The aim of this study was to describe the surface features of the peritoneal mesothelium covering the genital tract and adjacent ligaments of the sow to find signs of biosynthetic activation of cells. Surface features of the serosa covering the genital tract and adjacent ligaments from 14 cyclic sows, 7 in the follicular phase and 7 in the luteal phase of the estrous cycle, were examined by histology and scanning electron microscopy. Five additional sows, three in the follicular phase and two in the luteal phase of the estrous cycle, were examined by transmission electron microscopy (TEM). In this study, the presence of cells of the oviductal epithelium in the serosa of the infundibulum and the ampulla, as well as indications of a high functional activity of the mesothelial cells in the areas studied were two aspects that differed from the findings of previous works. Presence of endosalpingeal cells was observed in the serosal surface, showing cyclical variations with a predominance of either ciliated cells during the follicular phase or secretory cells during the luteal phase. Signs of high functional activity of the mesothelial cells included the predominance of cuboidal over flattened cells, a cytoplasm richly supplied with organelles, a dense microvillous coat, numerous primary cilia, and many secretory structures on the surface of cells. These results indicate that the serosa covering the genital area and the adjacent ligaments in the sow has an active epithelium whose coordinating role between reproductive tissues may be far more significant than previously thought. Anat Rec, 2007. © 2007 Wiley-Liss, Inc. [source] Reproductive Functions of Corticotropin-Releasing Hormone.AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2004Potential Clinical Utility of Antalarmins (CRH Receptor Type 1 Antagonists), Research Background:, The hypothalamic-pituitary-adrenal (HPA) axis exerts a complex, mostly inhibitory, effect on the female reproductive system. In addition, the principal regulator of this axis, the hypothalamic neuropeptide corticotropin-releasing hormone (CRH) and its receptors have been identified in most female reproductive tissues, including the ovary, uterus, and placenta. Furthermore, CRH is secreted in peripheral inflammatory sites where it exerts strong inflammatory actions. Antalarmins (CRH receptor type 1 antagonists) have been used to elucidate the roles of CRH in stress, inflammation and reproduction. Method of study:, We review existing data on the effects of CRH in the female reproductive system. Results:, Ovarian CRH participates in female sex steroid production, follicular maturation, ovulation and luteolysis. Uterine CRH participates in decidualization, implantation, and early maternal tolerance. Placental CRH participates in the physiology of pregnancy and the onset of parturition. Circulating placental CRH is secreted mostly during the latter half of pregnancy and is responsible for the concurrently increasing physiologic hypercortisolism of this period. After labor and delivery, this hypercortisolism is ensued by a transient suppression of hypothalamic CRH secretion, which may explain the postpartum blues and depression and the increased autoimmune manifestations depression of period, the postpartum period. Conclusions:, These data show that CRH is present in female reproductive tissues, and is regulating key reproductive functions with an inflammatory component, such as ovulation, luteolysis, implantation, and parturition. [source] The S -methylmethionine cycle in angiosperms: ubiquity, antiquity and activityTHE PLANT JOURNAL, Issue 5 2001Philippe Ranocha Summary Angiosperms synthesize S- methylmethionine (SMM) from methionine (Met) and S- adenosylmethionine (AdoMet) in a unique reaction catalyzed by Met S- methyltransferase (MMT). SMM serves as methyl donor for Met synthesis from homocysteine, catalyzed by homocysteine S- methyltransferase (HMT). MMT and HMT together have been proposed to constitute a futile SMM cycle that stops the free Met pool from being depleted by an overshoot in AdoMet synthesis. Arabidopsis and maize have one MMT gene, and at least three HMT genes that belong to two anciently diverged classes and encode enzymes with distinct properties and expression patterns. SMM, and presumably its cycle, must therefore have originated before dicot and monocot lineages separated. Arabidopsis leaves, roots and developing seeds all express MMT and HMTs, and can metabolize [35S]Met to [35S]SMM and vice versa. The SMM cycle therefore operates throughout the plant. This appears to be a general feature of angiosperms, as digital gene expression profiles show that MMT and HMT are co-expressed in leaves, roots and reproductive tissues of maize and other species. An in silico model of the SMM cycle in mature Arabidopsis leaves was developed from radiotracer kinetic measurements and pool size data. This model indicates that the SMM cycle consumes half the AdoMet produced, and suggests that the cycle serves to stop accumulation of AdoMet, rather than to prevent depletion of free Met. Because plants lack the negative feedback loops that regulate AdoMet pool size in other eukaryotes, the SMM cycle may be the main mechanism whereby plants achieve short-term control of AdoMet level. [source] | ||||||||||||||||||||||||||||