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Recombinase Activity (recombinase + activity)
Kinds of Recombinase Activity Selected AbstractsEndothelium-specific Cre recombinase activity in flk-1-Cre transgenic miceDEVELOPMENTAL DYNAMICS, Issue 2 2004Alexander H. Licht Abstract The use of the Cre-loxP recombination system allows the conditional inactivation of genes in mice. The availability of transgenic mice in which the Cre recombinase expression is highly cell type specific is a prerequisite to successfully use this system. We previously have characterized regulatory regions of the mouse flk-1 gene sufficient for endothelial cell-specific expression of the LacZ reporter gene in transgenic mice. These regions were fused to the Cre recombinase gene, and transgenic mouse lines were generated. In the resulting flk-1-Cre transgenic mice, specificity of Cre activity was determined by cross-breeding with the reporter mouse lines Rosa26R or CAG-CAT-LacZ. We examined double-transgenic mice at different stages of embryonic development (E9.5,E16.5) and organs of adult animals by LacZ staining. Strong endothelium-specific staining of most vascular beds was observed in embryos older than E11.5 in one or E13.5 in a second line. In addition, the neovasculature of experimental BFS-1 tumors expressed the transgene. These lines will be valuable for the conditional inactivation of floxed target genes in endothelial cells of the embryonic vascular system. Developmental Dynamics 229:312,318, 2004. © 2004 Wiley-Liss, Inc. [source] Cre-mediated recombination in pituitary somatotropesGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2009Igor O. Nasonkin Abstract We report a transgenic line with highly penetrant cre recombinase activity in the somatotrope cells of the anterior pituitary gland. Expression of the cre transgene is under the control of the locus control region of the human growth hormone gene cluster and the rat growth hormone promoter. Cre recombinase activity was assessed with two different lacZ reporter genes that require excision of a floxed stop sequence for expression: a chick ,-actin promoter with the CMV enhancer transgene and a ROSA26 knock-in. Cre activity is detectable in the developing pituitary after initiation of Gh transcription and persists through adulthood with high penetrance in Gh expressing cells and lower penetrance in lactotropes, a cell type that shares a common origin with somatotropes. This Gh-cre transgenic line is suitable for efficient, cell-specific deletion of floxed regions of genomic DNA in differentiated somatotropes and a subset of lactotrope cells of the anterior pituitary gland. genesis 47:55,60, 2009. © 2008 Wiley-Liss, Inc. [source] Transgenic expression of Cre recombinase in mitral/tufted cells of the olfactory bulbGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2005Yumiko Nagai Abstract Olfactory information is conveyed from the periphery to the olfactory cortices through mitral and tufted (M/T) cells in the olfactory bulb. A mouse with a specific expression of Cre recombinase in M/T cells is essential for genetic marking of M/T cells and manipulating their properties. Protocadherin 21 (Pcdh21) expression is highly restricted to M/T cells. Here we report a transgenic mouse line, Pcdh21-Cre, in which ,10-kb mouse Pcdh21 promoter drives the expression of Cre recombinase. In Pcdh21-Cre mice, Cre recombinase activity is predominantly detected in M/T cells, visualized with the anti-CFP immunostaining in offspring of a cross between Pcdh21-Cre and the reporter Rosa26-loxP-stop-loxP-CFP strain. These results demonstrate that the ,10-kb Pcdh21 promoter can drive transcription in M/T cells and Pcdh21-Cre mice can be used to excise floxed DNA fragments in M/T cells, which provides a valuable tool to reveal the structure and function of the central olfactory circuits. genesis 43:12,16, 2005. © 2005 Wiley-Liss, Inc. [source] Preparation of enzymatically active human Myc-tagged-NCre recombinase exhibiting immunoreactivity with anti-Myc antibodyMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2006Satoshi Watanabe Abstract The Cre- loxP system has been recognized as a tool for conditional gene targeting in mice. However, most anti-Cre antibodies fail to react with Cre expressed in vivo. In an attempt to directly detect Cre by antibodies in vivo, we constructed the tagged-NCre (NCreMH) gene by connecting the human Myc and His tag sequences to the 3, end of the NCre gene carrying a nuclear localizing signal (NLS) sequence. The production of NCre protein and the recombinase activity were detected after co-transfection with pCMV-NCreMH and pCETZ-17 carrying the loxP -flanked lacZ gene into NIH3T3 cells. This activity was also confirmed in vivo after gene transfer of pCMV-NCreMH and pCRTEIL-6 carrying loxP -flanked HcRed1 and EGFP cDNAs, into oviductal epithelium by electroporation. Immunohistochemical staining using anti-Myc antibody demonstrated that the area positive for enhanced green fluorescent protein (EGFP) fluorescence was immunostained with the antibody. These findings indicate that NCreMH is useful as an alternative to NCre for gene targeting. Mol. Reprod. Dev. 73: 1345,1352, 2006. © 2006 Wiley-Liss, Inc. [source] Clinical and genetic heterogeneity in Omenn syndrome and severe combined immune deficiencyPEDIATRIC TRANSPLANTATION, Issue 2 2009Tanja A. Gruber Abstract:, OS has been described as a clinical phenotype in infants characterized by SCID, diffuse erythroderma, and other distinct features. The pathogenesis is secondary to autologous, auto-reactive T cells produced as rare escapees from the SCID blockade. Mutations in either the RAG1 or RAG2 gene that lead to partial recombinase activity are responsible for many of the patients with these clinical features. We report on two patients, one with an atypical phenotype of OS (absence of rash but presence of other typical features) who harbored a previously undescribed mutation in RAG1, and a second who had many of the classic features of OS but was found to have a mutation in the common gamma chain (,c) cytokine receptor gene. These cases highlight the clinical and genetic heterogeneity of OS. [source] Expression of Cre Recombinase in Pigment CellsPIGMENT CELL & MELANOMA RESEARCH, Issue 4 2002Laurence Guyonneau Conditional gene targeting using the Cre/loxP system enables specific deletion of a gene in a tissue of interest. For application of Cre-mediated recombination in pigment cells, Cre expression has to be targeted to pigment cells in transgenic mice. So far, no pigment cell-specific Cre transgenic line has been reported and we present and discuss our first results on use of Cre recombinase in pigment cells. A construct was generated where Cre recombinase is controlled by the promoter of the mouse dopachrome tautomerase (Dct) gene. The construct was functionally tested in vitro and introduced into mice. Following breeding to two reporter mouse strains, we detected Cre recombinase activity in telencephalon, melanoblasts, and retinal pigment epithelium (RPE). Our data demonstrate the feasibility of pigment cell-specific Cre/loxP-mediated recombination. [source] |