The testis-specific apoptosis related gene TTL.6 underwent adaptive evolution in the lineage leading to humans

The TTL.6 gene is a member of the tubulin-tyrosine ligase (TTL) family involved in apoptosis and preferentially expressed in the testis. We sequenced the coding region and part of the introns of TTL.6 in world wide human populations and five representativ

Rapid evolution of mammalian X-linked testis microRNAs

Background: MicroRNAs (miRNAs), which are small, non-coding RNAs approximately 21-nucleotides in length, have become a major focus of research in molecular biology. Mammalian miRNAs are proposed to regulate approximately 30% of all protein-coding genes. P

Expression and regulation of orphan receptor TR2 mRNA in germ cells of cryptorchid testis in rat and rhesus monkey

Expression and cellular localization of orphan receptor TR2 mRNA in relation to germ cell apoptosis in cryptorchid testes of rat and rhesus monkey have been studied by using in situ hybridization and in situ 3'-end labeling of DNA fragments (TUNEL). The results show that: (i) TR2 mRNA is specifically expressed in the germ cells, mainly in the spermatocytes, round and elongated spermatids. The expression level of TR2 mRNA varies with the seminiferous cycle, (ii) In the rat cryptorchid testes on days 3 and 5 after the surgery, the germ cells began to undergo apoptosis with no evident decrease in TR2 mRNA level. On day 7.5, however, most germ cells underwent apoptosis, while the expression level of TR2 mRNA declined markedly, and TR2 mRNA was rarely expressed on day 10 thereafter. (iii) On days 15 and 20 of the cryptorchid testes of rhesus monkey, TR2 mRNA was only expressed in a few of primary spermatocytes and the mRNA was almost undetectable on days 30, 45, 60. These results suggest that TR2 mRNA probably plays an important role in spermatogenesis and germ cell apoptosis.

In vivo study on the effects of microcystin extracts on the expression profiles of proto-oncogenes (c-fos, c-jun and c-myc) in liver, kidney and testis of male Wistar rats injected i.v. with toxins

Microcystins (MCs) are a potent liver tumor promoter, possessing potent tumor-promoting activity and weak initiating activity. Proto-oncogenes are known to be involved in the tumor-promoting mechanisms of microcystin-LR. However, few data are available on the effects of MCs oil proto-oncogenes in the whole animal. To investigate the effects of MCs on the expression profile of the proto-oncogenes in different organs, male Wistar rats were injected intravenously with microcystin extracts at a dose of 86.7 mu g MC-LR eq/kg bw (MC-LR eq, MC-LR equivalents). mRNA levels of three proto-oncogenes c-fos, c-jun and c-myc in liver, kidney and testis were analyzed using quantitative real-time PCR at several time points post-injection. Significant induction of these genes at transcriptional level was observed in the three organs. In addition, the increase of mRNA expression of all three genes was much higher in liver than in kidney and testis. Meanwhile, the protein levels of c-Fos and c-Jun were investigated by western blotting. Both proteins were induced in the three organs. However, elevations of protein levels were Much lower than those of mRNA levels. These findings suggest that the expression of c-fos, c-jun and c-myc might be one possible mechanism for the tumor-promoting activity and initiating activity of microcystins. (c) 2008 Published by Elsevier Ltd.

Induction of cytogenetic adaptive response in spermatogonia and spermatocytes by pre-exposure of mouse testis to low-dose C-12(6+) ions

To investigate the effects of pre-exposure of mouse testis to low-dose C-12(6+) ions on cytogenetics of spermatogonia and spermatocytes induced by subsequent high-dose irradiation. the testes of outbred Kun-Ming strain mice were irradiated with 0.05 Gy of C-12(6+) ions as the pre-exposure dose, and then irradiated with 2 Gy as challenging dose at 4 h after per-exposure. Poly(ADP-ribose) polymerase (PARPs) activity and PARP-1 protein expression were respectively measured by using the enzymatic and Western blot assays at 4 h after irradiation; chromosomal aberrations in spermatogonia and spermatocytes were analyzed by the air-drying method at 8 h after irradiation. The results showed that there was a significant increase in the frequency of chromosomal aberrations and significant reductions of PARP activity and PARP-1 expression level in the mouse testes irradiated with 2 Gy of C-12(6+) ions. However, pre-exposure of mouse testes to a low dose of C-12(6+) ions significantly increased PARPs activity and PARP-1 expression and alleviated the harmful effects induced by a subsequent high-dose irradiation. PARP activity inhibitor 3-aminobenzamide (3-AB) treatment blocked the effects of PARP-1 on cytogenetic adaptive response induced by low-dose C-12(6+) ion irradiation. The data suggest that pre-exposure of testes to a low dose of heavy ions can induce cytogenetic adaptive response to subsequent high-dose irradiation. The increase of PARP-1 protein induced by the low-dose ionizing irradiation may be involved in the mechanism of these observations. (C) 2008 Elsevier B.V. All rights reserved.

Rapid evolution, genetic variations, and functional association of the human spermatogenesis-related gene NYD-SP12

NYD-SP12 is a recently identified spermatogenesis-related gene with a pivotal role in human testis development. In this study, we analyzed between-species divergence and within-species variation of NYD-SP12 in seven representative primate species, four wo

Adaptive evolution of SCML1 in primates, a gene involved in male reproduction

Background: Genes involved in male reproduction are often the targets of natural and/or sexual selection. SCML1 is a recently identified X-linked gene with preferential expression in testis. To test whether SCML1 is the target of selection in primates, we

Proteomic Analysis of Proteins Involved in Spermiogenesis in Mouse

Spermiogenesis is a unique process in mammals during which haploid round spermatids mature into spermatozoa in the testis. Its successful completion is necessary for fertilization and its malfunction is an important cause of male infertility. Here, we report the high-confidence identification of 2116 proteins in mouse haploid germ cells undergoing spermiogenesis: 299 of these were testis-specific and 155 were novel. Analysis of these proteins showed many proteins possibly functioning in unique processes of spermiogenesis. Of the 84 proteins annotated to be involved in vesicle-related events, VAMP4 was shown to be important for acrosome biogenesis by in vivo knockdown experiments. Knockdown of VAMP4 caused defects of acrosomal vesicle fusion and significantly increased head abnormalities in spermatids from testis and sperm from the cauda epididymis. Analysis of chromosomal distribution of the haploid genes showed underrepresentation on the X chromosome and overrepresentation on chromosome 11, which were due to meiotic sex chromosome inactivation and expansion of testis-expressed gene families, respectively. Comparison with transcriptional data showed translational regulation during spermiogenesis. This characterization of proteins involved in spermiogenesis provides an inventory of proteins useful for understanding the mechanisms of male infertility and may provide candidates for drug targets for male contraception and male infertility.

Transport of anti-sperm monoclonal IGA and IGC into murine male and female genital tracts from blood - Effect of sex hormones

Ab levels in the genital tract may be important in fertility and in preventing sexually transmitted diseases, In this study, I-125-labeled polymer or monomer mAb IgA (C4pIgA or C4mIgA) and IgC2b (C4IgC) to murine lactate dehydrogenase C4 and a polymer mAb IgA (npIgA) not cross-reacting with mouse sperm were intravenously injected into BALB/c mice, and the relative distribution of these Abs was determined. Polymer IgA was transported much more efficiently into the genital tract, trachea, and duodenum of both sexes than C4IgG and C4 mIgA (p < 0.01), The transport of polymer IgA (C4pIgA and npIgA) into the male genital tract greatly increased following orchiectomy (p < 0.01); this change was not affected by testosterone, suggesting that the unknown regulatory factor(s) from the testis may suppress polymer IgA transport, However, the transport of polymer IgA into female genital tissues was significantly decreased by ovariectomy (p < 0.01); this decline can be rectified by P-estradiol but not progesterone treatment, suggesting that estradiol may stimulate polymer IgA transport, Furthermore, the transport of C4IgG into tissues of the Fallopian tubes and the uterus was significantly decreased by treatment with progesterone (p < 0.01). Together, these findings indicate that serum polymer IgA can be transported selectively into the genital tracts of both sexes, that this transport is strongly under the control of gonads, and that transport of Ige into the Fallopian tubes and uterus is downregulated by progesterone.

Murine MyaK, a member of a family of yeast YAK1-related genes, is highly expressed in hormonally modulated epithelia in the reproductive system and in the embryonic central nervous system

We have cloned a mouse homologue (designated Myak) of the yeast protein kinase YAK1. The 1210 aa open reading frame contains a putative protein kinase domain, nuclear localization sequences and PEST sequences. Myak appears to be a member of a growing family of YAK1-related genes that include Drosophila and human Minibrain as well as a recently identified rat gene ANPK that encode a steroid hormone receptor interacting protein. RNA blot analysis revealed that Myak is expressed at low levels ubiquitously but at high levels in reproductive tissues, including testis, epididymis, ovary, uterus, and mammary gland, as well as in brain and kidney. In situ hybridization analysis on selected tissues revealed that Myak is particularly abundant in the hormonally modulated epithelia of the epididymis, mammary gland, and uterus, in round spermatids in the testis, and in the corpora lutea in the ovary, Myak is also highly expressed in the aqueduct of the adult brain and in the brain and spinal cord of day 12.5 embryos, Mol. Reprod. Dev. 55:372-378, 2000. (C) 2000 Wiley-Liss, Inc.

Involvement of Fas/FasL system in apoptotic signaling in testicular germ cells of male Wistar rats injected i.v. with microcystins

Previous studies have shown that gonads were the second target organ of microcystins (MCs), and that MCs exposure exerted obvious toxic effects on male reproductive system of mammals. However, relevant molecular evidences are still lacking. Fas-signaling pathway plays a key role in toxicant-induced germ cell apoptosis. This study was to evaluate the responses of Fas/FasL system related genes and proteins in testes of rats injected intravenously with MCs. Enhanced apoptosis of germ cells in the testes of MCs-treated rats was detected by the terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling (TUNEL) associated with up-regulation of the Fas/FasL system. Both Fas and FasL protein expression were induced evidently from I h post-injection, and this high expression level maintained throughout the experiment. In addition, the activation of caspase-8 and caspase-3 protein was also observed, which were indicators of apoptosis. These results suggested the likely involvement of Fas/FasL system in the MCs-induced germ cell apoptosis. It is also suggested that MCs can cause damage to Sertoli cells directly. (C) 2009 Elsevier Ltd. All rights reserved.

Expression pattern of cellular nucleic acid-binding protein (CNBP) during embryogenesis and spermatogenesis of gibel carp

By differential screening, we cloned the CagCNBP, demonstrated its predominant expression in ovary and testis, and reported its development behavior during folliculogenesis and oogenesis by immunofluorescence localization (Liu and Gui, Gene 365:181-192, 2005), but its developmental behavior during spermatogenesis and its transcript distribution during embryogenesis are not revealed. In the present study, by in situ hybridization, we analyze CagCNBP expression pattern during gibel carp embryogenesis. The CagCNBP transcripts ubiquitously distributed in all embryonic cells in early developmental stage embryos, and peak in midbrain, hindbrain and somites of gibel carp larva during organogenesis. By antibody detection, we reveal CagCNBP protein distribution change during spermatogenesis. The cell-specific distribution of CagCNBP is revealed by immunofluorescence staining, and predominant CagCNBP expression in testis somatic cells and spermatogonia is demonstrated in this paper. For the first time, the CNBP distribution during spermatogenesis in vertebrate has been revealed.

Grass carp reovirus activates RNAi pathway in rare minnow, Gobiocypris rarus

Dicer catalyzes the initiation step of RNA interference (RNAi) which is known to play a significant role in innate immune response to viral infection in many organisms. To study the RNAi-related pathway after virus infection in fish, we identified a partial cDNA sequence of dicer from rare minnow, Gobiocypris rants. Real-time quantitative RT-PCR (qRT-PCR) demonstrated the Dicer transcript level was the highest at zygote stage, decreased at prim-5 stage, and was stable from the protruding mouth to adult stage. Regular RT-PCR analysis showed that the Dicer gene expressed widely in the tested tissues, including brain, gill, heart, intestine, kidney, liver, muscle, ovary, spleen and testis. The expression of Dicer mRNA was significantly increased in the early period of Grass carp reovirus (GCRV) infection, and declined from 24 It post-injection (h p.i.) (P<0.05). The mRNA expression returned to control levels at 48 h p.i. (P>0.05). Under transmission electron microscope, virions were difficulty to find out in 12 h p.i., and virus inclusion bodies and few scattered viral particles were easily visualized from 24 h p.i. to moribund. These results implied GCRV triggered the RNAi pathway in the early stages of infection and perhaps virus inclusion bodies suppressed the antiviral functions of RNAi mechanism. (C) 2009 Published by Elsevier B.V.

A new species of Allocreadium (Trematoda : Allocreadiidae) from freshwater fishes in the Danjiangkou Reservoir in China

A new species of Allocreadium, Allocreadium danjiangensis n. sp., is described from the intestine of several species of freshwater fish, including Abbottina rivularis (Basilewsky, 1855), Sarcocheilichthys nigripinnis nigripinns (Gunther, 1873), Gnathopogon argentatus (Sauvage et Dabry 1874), Opsariichthys uncirostris bidens (Gunther, 1873), and Erythroculter mongolicus mongolicus (Basilewsky, 1855) (Cyprinidae) from the Danjiangkou Reservoir in central China. The main morphological characters of the new species are as follows: vitelline follicles numerous, extending from the level of acetabulum to posterior extremity, distributed over both sides around the ceca; cirrus sac relatively large, developed, lying obliquely anterior to the acetabulum, extending from the level of the intestinal bifurcation to the central level of acetabulum, and overlapping left or right cecal; and ovary much smaller than testes, generally close to or even overlapping the anterior border of anterior testis. Observation by scanning electron microscopy shows only 2 kinds of tegumental formations, i.e., papillae and tubercles, instead of 3 types of tegumental formations, i.e., papillae, bosses, and minute sensor receptors observed on other species of the Allocreadiidae. The tegumental striations of the present species vary on the different parts of the body. In addition, a new structure, identified as the "groove" with a tonguelike tubercle, was observed on the inner wall of acetabulum.

Antisense for gonadotropin-releasing hormone reduces gonadotropin synthesis and gonadal development in transgenic common carp (Cyprinus carpio)

Generating transgenic fish with desirable traits (e.g., rapid growth, larger size, etc.) for commercial use has been hampered by concerns for biosafety and competition if these fish are released into the environment. These obstacles may be overcome by producing transgenic fish that are sterile, possibly by inhibiting hormones related to reproduction. In vertebrates, synthesis and release of gonadotropin (GtH) and other reproductive hormones is mediated by gonadotropin-releasing hormone (GnRH). Recently two cDNA sequences encoding salmon-type GnRH (sGnRH) decapeptides were cloned from common carp (Cyprinus carpio). This study analyzed the expression of these two genes using real-time polymerase chain reaction (RT-PCR) in different tissues carp at varying developmental stages. Transcripts of both genes were detected in ovary and testis in mature and regressed, but not in juvenile carp. To evaluate the effects of sGnRH inhibition, the recombinant gene CAsGnRHpc-antisense, expressing antisense sGnRH RNA driven by a carp beta-actin promoter, was constructed. Blocking sGnRH expression using antisense sGnRH significantly decreased GtH in the blood of male transgenic carp. Furthermore, some antisense transgenic fish had no gonadal development and were completely sterile. These data demonstrate that sGnRH is important for GtH synthesis and development of reproductive organs in carp. Also, the antisense sGnRH strategy may prove effective in generating sterile transgenic fish, eliminating environmental concerns these fish may raise. (c) 2007 Published by Elsevier B.V.