Horikawa M, et al reported the Mouse Germ-Cell-Specific Leucine-Rich Repeat Protein NALP14: A Member of the NACHT Nucleoside Triphosphatase Family.
Microscopy of sectioned neonatal mouse ovaries established the predominance of primordial follicles in day 3 samples and the predominance of primary follicles by day 8. To identify genetic determinants of the primordial to primary follicle transition, the transcriptome of day 1 or day 3 mouse ovaries was contrasted by differential display with that of day 8 ovaries. This manuscript examines one of the upregulated genes, the novel gc-lrr (germ cell leucine-rich repeat) gene whose transcript displayed 18- and 127-fold increments from day 1 to days 3 and 8, respectively. First noted by in situ in oocytes encased by primary follicles, gc-lrr transcripts were continuously expressed through the pre-ovulatory stage. The transcripts declined upon the resumption of meiotic maturation and were markedly diminished by the 2-cell embryo. The corresponding 3,281bp full-length cDNA coded for a 993 residue/104.6kDa germ cell specific protein. A member of the multifunctional NACHT NTPase family, the GC-LRR protein featured 14 iterations of the LRR domain, a region implicated in protein-protein interaction. Protein BLAST analysis of the GC-LRR sequence revealed 2 previously reported germ cell-specific homologs i.e. MATER (Maternal Antigen That Embryos Require) and Rnh2 (RiboNuclease/Angiogenin Inhibitor 2). The structural attributes, expression pattern, as well as the cellular localization of MATER and Rnh2, largely conformed to those reported for GC-LRR.
General function
Enzyme
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Cellular localization
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Ovarian function
Follicle development
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Expression regulated by
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Ovarian localization
Oocyte
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Genomewide discovery and classification of candidate ovarian fertility genes in the mouse. Gallardo TD et al. Female infertility syndromes are among the most prevalent chronic health disorders in women, but their genetic basis remains unknown because of uncertainty regarding the number and identity of ovarian factors controlling the assembly, preservation, and maturation of ovarian follicles. To systematically discover ovarian fertility genes en masse, we employed a mouse model (Foxo3) in which follicles are assembled normally but then undergo synchronous activation. We developed a microarray-based approach for the systematic discovery of tissue-specific genes and, by applying it to Foxo3 ovaries and other samples, defined a surprisingly large set of ovarian factors (n = 348, approximately 1% of the mouse genome). This set included the vast majority of known ovarian factors, 44% of which when mutated produce female sterility phenotypes, but most were novel. Comparative profiling of other tissues, including microdissected oocytes and somatic cells, revealed distinct gene classes and provided new insights into oogenesis and ovarian function, demonstrating the utility of our approach for tissue-specific gene discovery. This study will thus facilitate comprehensive analyses of follicle development, ovarian function, and female infertility. This is an oocyte-specific gene.