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Cytoplasmic Distribution (cytoplasmic + distribution)
Selected AbstractsMaternal expression and function of the Drosophila sox gene Dichaete during oogenesisDEVELOPMENTAL DYNAMICS, Issue 10 2006Ashim Mukherjee Abstract Members of the Sox family of DNA-binding HMG domain proteins have been shown to regulate gene transcription in a wide range of developmental processes, including sex determination, neurogenesis, and chondrogenesis. However, little is known about their potential functions in developing germline tissues. In Drosophila, the Sox protein Dichaete (a.k.a., Fish-hook) is a member of the SoxB subgroup whose HMG domain shares strong sequence similarity to that of vertebrate Sox2. Dichaete exhibits dynamic expression in embryonic and larval stages and has pleiotropic functions in a variety of tissues. In this study, we extend analyses of Dichaete function and show that expression of Dichaete protein is detected in the developing oocyte during early to mid stages of oogenesis. Strikingly, Dichaete exhibits cytoplasmic distribution and is not detected in the oocyte nucleus. Germline mosaic analyses revealed that the Dichaete gene has maternal functions that influence dorsal/ventral patterning of the egg chamber. Dichaete mutant eggs exhibit defects in formation of the dorsal appendages, differentiation of dorsal/anterior follicle cells, and mislocalization of Gurken protein and gurken mRNA. Dichaete protein was shown to possess RNA-binding capabilities, suggesting a direct post-transcriptional role in regulating RNA functions. Developmental Dynamics 235:2828,2835, 2006. © 2006 Wiley-Liss, Inc. [source] The proteasome inhibitor, MG132, promotes the reprogramming of translation in C2C12 myoblasts and facilitates the association of hsp25 with the eIF4F complexFEBS JOURNAL, Issue 17 2004Joanne L. Cowan The eukaryotic translation initiation factor (eIF) 4E, is regulated by modulating both its phosphorylation and its availability to interact with the scaffold protein, eIF4G, to form the mature eIF4F complex. Here we show that treatment of C2C12 myoblasts with the proteasomal inhibitor, MG132 (N -carbobenzoxyl-Leu-Leu-leucinal), resulted in an early decrease in protein synthesis rates followed by a partial recovery, reflecting the reprogramming of translation. The early inhibition of protein synthesis was preceded by a transient increase in eIF2, phosphorylation, followed by a sustained increase in eIF4E phosphorylation. Inhibition of eIF4E phosphorylation with CGP57380 failed to prevent translational reprogramming or the moderate decrease in eIF4F complexes at later times. Prolonged incubation with MG132 resulted in the increased expression of heat shock protein (hsp)25, ,B-crystallin and hsp70, with a population of hsp25 associating with the eIF4F complex in a p38 mitogen-activated protein kinase-dependent manner. Under these conditions, eIF4GI, and to a lesser extent eIF4E, re-localized from a predominantly cytoplasmic distribution to a more perinuclear and granular staining. Although MG132 had little effect on the colocalization of eIF4E and eIF4GI, it promoted the SB203580-sensitive association of eIF4GI and hsp25, an effect not observed with ,B-crystallin. Addition of recombinant hsp25 to an in vitro translation assay resulted in stimulation of on-going translation and a moderate decrease in de novo translation, indicating that this modified eIF4F complex containing hsp25 has a role to play in recovery of mRNA translation following cellular stress. [source] Expression profiling correlates with treatment response in women with advanced serous epithelial ovarian cancerINTERNATIONAL JOURNAL OF CANCER, Issue 4 2006Tanya R. Newton Abstract The majority of epithelial ovarian carcinomas are of serous subtype, with most women presenting at an advanced stage. Approximately 70% respond to initial chemotherapy but eventually relapse. We aimed to find markers of treatment response that might be suitable for routine use, using the gene expression profile of tumor tissue. Thirty one women with histologically-confirmed late-stage serous ovarian cancer were classified into 3 groups based on response to treatment (nonresponders, responders with relapse less than 12 months and responders with no relapse within 12 months). Gene expression profiles of these specimens were analyzed with respect to treatment response and survival (minimum 36 months follow-up). Patients' clinical features did not correlate with prognosis, or with specific gene expression patterns of their tumors. However women who did not respond to treatment could be distinguished from those who responded with no relapse within 12 months based on 34 gene transcripts (p < 0.02). Poor prognosis was associated with high expression of inhibitor of differentiation-2 (ID2) (p = 0.001). High expression of decorin (DCN) and ID2 together was strongly associated with reduced survival (p = 0.003), with an estimated 7-fold increased risk of dying (95% CI 1.9,29.6; 14 months survival) compared with low expression (44 months). Immunohistochemical analysis revealed both nuclear and cytoplasmic distribution of ID2 in ovarian tumors. High percentage of nuclear staining was associated with poor survival, although not statistically significantly. In conclusion, elevated expression of ID2 and DCN was significantly associated with poor prognosis in a homogeneous group of ovarian cancer patients for whom survival could not be predicted from clinical factors. © 2006 Wiley-Liss, Inc. [source] An immunohistochemical study of laminin in basal cell carcinomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2010Wedad Z. Mostafa Background: Laminins are components of the extracellular matrix that mediate cell adhesion, growth, migration, proliferation and differentiation. Basement membrane (BM) laminins, in particular, may play a role in enhancing carcinoma cell motility. Aim: To evaluate the distribution pattern of laminin in basal cell carcinoma (BCC), as regards the basement membrane, cellular cytoplasm, peritumoral lacunae and surface epithelium and to correlate laminin distribution with different variants of BCC. Patients and Methods: Skin biopsy specimens were obtained from 21 BCC patients for routine histopathological and immunohistochemical study. Laminin was evaluated qualitatively and semiquantitatively using monoclonal mouse antihuman antibody (Dako-Laminin, 4C7. Code No: MO638, which reacts with the terminal globular domain of the ,5 chain) Results: The majority of BCC cases showed patchy cytoplasmic distribution of laminin. The BM expression of laminin, in most cases, was well defined, fine and linear with irregular areas of thickening. Staining intensity was moderate in differentiated and mixed variants, weak in superficial spreading and absent in morpheic types. Conclusion: Cytoplasmic and basement membrane laminin is important in the pathogenesis and invasion of BCC. Most laminin was in basement membrane zone (BMZ), and the more differentiated the tumor, the more cytoplasmic and BM staining it expressed. [source] Upregulation of immunoreactivity of endothelin-1 and ,-SMA in PDL microvasculature following acute tooth loading: an immunohistochemical study in the marmosetORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2003MR Sims Structured Abstract Authors , Sims MR, Ashworth JF, Sampson WJ Objectives , To test the hypothesis that a continuous mechanical tooth load would elevate immunoreactivity of endothelin-1 (ET-1) and alpha-smooth muscle actin (,-SMA) in the periodontal ligament (PDL) microvasculature. Design , A randomized control study employing 1.5 h of loading to first molars. Setting and Sample Population , Orthodontic Research Laboratory, Dental School, Adelaide University. Four young adult, male marmoset monkeys were consecutively anaesthetized and treated. Experimental Variable , An external telescoping frame applied a jaw closing load (120,200 g) transmitted occlusally, via a rubber pad, to randomly assigned mandibular left or right first molars. Contralateral molars were used as controls. Outcome Measure , Undemineralized, midsagittal, mandibular molar slices, ,150 ,m thick were immunolabelled with ET-1 and ,-SMA antibodies and examined in a confocal laser scanning microscope (CLSM) for vascular endothelium and smooth muscle immunolabelling. Results , Three categories of post-capillary-sized venule endothelial cell immunolabelling occurred: endothelium labelled solely with ET-1; endothelium labelled solely with ,-SMA; endothelium labelled with both ET-1 and ,-SMA. In endothelial cells, the ,-SMA showed a moderate cytoplasmic distribution with dense peripheral concentration. Loading increased arteriole ,-SMA actin labelling. Conclusion , Scattered expression of ET-1 is the default state in primate PDL endothelial cells. Increased antigenicity of endothelial cells to both ET-1 and ,-SMA, and of arteriolar smooth muscle to ,-SMA, is a response to shear and compression loads. [source] | ||||||||||