Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.13 (protein kinase C)
 49,245 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The putative roles of different signal transduction pathways in the regulation of testicular androgen production in goldfish were investigated. In addition to the role of the gonadotropin-adenylate cyclase pathway, which was studied using human chorionic gonadotropin and forskolin, we determined the effects of changes in intracellular calcium content and protein kinase C activation on androgen production using calcium ionophore A23187 and phorbol 12-myristate 13-acetate (PMA), respectively. Testis fragments incubated in vitro respond to hCG in a time- and dose-dependent manner with a resultant increase in the secretion of testosterone (T) and 11-ketotestosterone (11-KT). Although ineffective alone, PMA (400 nM) and A23187 (4000 nM) stimulate a small but significant increase (3-fold above basal) in T production. This response is minor compared to the up to 200-fold increase in T secretion observed in response to either hCG or forskolin. PMA (25-400 nM) alone and A23187 (250-4000 nM) alone inhibit the stimulatory actions of hCG on T production. Unlike PMA, the inactive phorbol 4 alpha-phorbol didecanoate, which does not activate PKC, had no effect on hCG-stimulated T production. PMA and A23187 did not influence the effects of forskolin on T production, suggesting that the compounds exert their effects prior to adenylate cyclase activation. In summary, the present studies suggest that in addition to the stimulatory actions of the adenylate cyclase second messenger system, changes in intracellular calcium content and protein kinase C activation may modulate testicular androgen production in the goldfish.
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PMID:The control of testicular androgen production in the goldfish: effects of activators of different intracellular signalling pathways. 193 14

Testes of lepidoptera synthesized ecdysteroid in a somewhat different temporal pattern than the prothoracic glands that release ecdysteroid to the hemolymph. Brain extracts from Heliothis virescens and Lymantria dispar induced testes to synthesize ecdysteroid, but did not affect prothoracic glands. The testis ecdysiotropin (LTE) was isolated from L. dispar pupal brains by a series of high-pressure chromatography steps. Its sequence was Ile-Ser-Asp-Phe-Asp-Glu-Tyr-Glu-Pro-Leu-Asn-Asp-Ala-Asp-Asn-Asn-Glu-Val-Leu-Asp-Phe-OH, of molecular mass 2,473 Daltons. The predominant signaling pathway for LTE was via G(i) protein, IP3, diacylglycerol and PKC; a modulating pathway, apparently mediated by an angiotensin II-like peptide, was controlled via G(s) protein, cAMP, and PKA. Testis ecdysteroid caused isolated testis sheaths to also synthesize a growth factor that induced development of the male genital tract. The growth factor appeared to be a glycoprotein similar to vertebrate alpha-1-glycoprotein. A polyclonal antibody to LTE indicated LTE-like peptide in L. dispar brain medial neurosecretory cells, the suboesophageal, and other ganglia, and also in its target organ, the testis sheath. LTE immunoreactivity was also seen in testis sheaths of Rhodnius prolixus. LTE-like immunoactivity was also detected in developing optic lobes, antennae, frontal ganglia, and elongating spermatids of developing L. dispar pupae. This may indicate that LTE has a role in development as well as stimulation of testis ecdysteroid synthesis. Published 2001 Wiley-Liss, Inc.
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PMID:Testis ecdysiotropin, an insect gonadotropin that induces synthesis of ecdysteroid. 1146 22

The expression of stage-specific genes during spermatogenesis was determined by isolating two segments of rat seminiferous tubule at different stages of the germinal epithelium cycle delineated by transillumination-delineated microdissection, combined with differential display polymerase chain reaction to identify the differential transcripts formed. A total of 22 cDNAs were identified and accepted by GenBank as new expressed sequence tags. One of the expressed sequence tags was radiolabeled and used as a probe to screen a rat testis cDNA library. A novel full-length cDNA composed of 2228 bp, designated as RSD-3 (rat sperm DNA no.3, GenBank accession no. AF094609) was isolated and characterized. The reading frame encodes a polypeptide consisting of 526 amino acid residues, containing a number of DNA binding motifs and phosphorylation sites for PKC, CK-II, and p34cdc2. Northern blot of mRNA prepared from various tissues of adult rats showed that RSD-3 is expressed only in the testis. The initial expression of the RSD-3 gene was detected in the testis on the 30th postnatal day and attained adult level on the 60th postnatal day. Immunolocalization of RSD-3 in germ cells of rat testis showed that its expression is restricted to primary spermatocytes, undergoing meiosis division I. A human testis homologue of RSD-3 cDNA, designated as HSD-3.1 (GenBank accession no. AF144487) was isolated by screening the Human Testis Rapid-Screen arrayed cDNA library panels by RT-PCR. The exon-intron boundaries of HSD-3.1 gene were determined by aligning the cDNA sequence with the corresponding genome sequence. The cDNA consisted of 12 exons that span approximately 52.8 kb of the genome sequence and was mapped to chromosome 14q31.3.
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PMID:A novel gene, RSD-3/HSD-3.1, encodes a meiotic-related protein expressed in rat and human testis. 1273 79