Biomedical subjects

Jiahao Sha

Publications and source records attributed to Jiahao Sha.

At least 19 recordsLinked to original sources

PubMed2006

Human testicular protein NYD-SP16 is involved in sperm capacitation and the acrosome reaction.

OBJECTIVE: To investigate the functional role of human testicular protein NYD-SP16. DESIGN: Controlled experimental study. SETTING: University research laboratory. ANIMAL(S): ICR strain of mice. INTERVENTION(S): Testicular tissue and sperms were collected from 12- to 16-week-old male mice; cumulus-oocyte complexes were harvested from mature female mice after inducing superovulation. MAIN OUTCOME MEASURE(S): Expression of NYD-SP16 in mouse testis was analyzed by immunohistochemistry, its localization in mouse sperm was evaluated by immunofluorescence, and the functional role of NYD-SP16 in the process of fertilization was determined by CTC staining and in vitro fertilization. RESULT(S): In mouse testis, NYD-SP16 was immunolocalized to elongating spermatids and the staining was confined to the head. Immunoreactivity in mouse sperm was mainly seen in the acrosomal region and this expression pattern was not altered in capacitated sperm. However, after the acrosome reaction (AR), the intensity of the fluorescence staining attenuated significantly. NYD-SP16 antiserum significantly inhibited mouse sperm capacitation and the AR in a concentration-dependent manner and the presence of anti-NYD-SP16 serum, during co-incubation of gametes, produced a concentration-dependent decrease in the percentage of zygotes. CONCLUSION(S): NYD-SP16 protein is a component of sperm acrosome, which plays a functional role in sperm capacitation and the AR and is consequently necessary for fertilization.

Acrosome Reaction↗

PubMed2006

NYD-SP15: a novel gene potentially involved in regulating testicular development and spermatogenesis.

By hybridizing human adult testis cDNA microarrays with human adult and embryo testis cDNA probes, we identified a novel human testis gene, NYD-SP15. NYD-SP15 expression was 3.26-fold higher in adult than in fetal testis; however, there was almost no NYD-SP15 expression in the sperm. NYD-SP15 comprises 3364 base pairs, including a 1545 bp open reading frame encoding a 514 amino acid protein possessing 89% sequence identity with the mouse testis homologous protein. NYD-SP15 is located on human chromosome 13q14.2. The deduced structure of the protein contains two dCMP_cyt_deam domains, indicating a potential functional role for zinc ion binding. The gene is expressed variably in a wide range of tissues, with high expression levels in the testis. Sequence analysis revealed that NYD-SP15 is not a highly conserved protein, with its distribution in high-level species such as vertebrates including Homo, Mus, Rattus, and Canis. The results of semiquantitative polymerase chain reaction in mouse testis representing different developmental stages indicate that NYD-SP15 expression was developmentally regulated. These results suggest the putative NYD-SP15 protein may play an important role in testicular development and spermatogenesis and may be an important factor governing male infertility.

Amino Acid Sequence↗

PubMed2006

A testis-specific and testis developmentally regulated tumor protein D52 (TPD52)-like protein TPD52L3/hD55 interacts with TPD52 family proteins.

Tumor protein D52-like proteins (TPD52) are small coiled-coil motif bearing proteins that were first identified in breast cancer. TPD52 and related proteins have been implicated in cell proliferation, apoptosis, and vesicle trafficking. To date, three human TPD52 members had been identified, named hD52 (TPD52), hD53 (TPD52L1), and hD54 (TPD52L2). The most important characteristic of the protein family is a highly conserved coiled-coil motif that is required for homo- and heteromeric interaction with other TPD52-like proteins. Herein, we identified a novel TPD52-like sequence (TPD52L3, or hD55) in human testis using cDNA microarray. Sequence analysis of the deduced protein suggests that hD55 contains a coiled-coil motif and is highly conserved compared with other TPD52-like sequences. Yeast two-hybrid and GST pull-down assays revealed that hD55 interacts with hD52, hD53, hD54, and itself. cDNA microarray detection found that hD55 was expressed at 5.6-fold higher levels in adult testis than in fetal testis. Additionally, the expression profile shows that hD55 is testis-specific, indicating a potential role for hD55 in testis development and spermatogenesis.

Aging↗

PubMed2006

Defective expression of Galpha12 in the testes of azoospermia patients and in the spermatozoa with low motility.

Antibody to the Galpha12-subunit of guanine nucleotide regulatory proteins was used to determine whether the Galpha12 is present in adult human spermatogenic cells and to determine its role in dyszoospermia. Immunoblots from testes and spermatozoa demonstrated the presence of Galpha12 in the samples. Immunohistochemical analyses of testes found that Galpha12 was expressed in the cytoplasm of Leydig cells and was expressed in spermatids from the elongating Sb phase to mature sperm. Indirect immunofluorescence of human spermatozoa revealed the presence of Galpha12 in the neck region and the midpiece of the sperm. Galpha12 in spermatids and spermatozoa partially co-localized with F-actin and alpha-tubulin. Immunohistochemical analyses of tissues from three patients with non-obstructive azoospermia showed abnormal expression of Galpha12 in more than 45% of spermatids. Furthermore, Western blots and indirect immunofluorescence found defective expression of Galpha12 in low-motility spermatozoa with midpieces that were bent on themselves. Therefore, it suggests that Galpha12 plays a role in polarity and tail formation as spermatids mature. Furthermore, Galpha12 may be a candidate protein responsible for azoospermia caused by spermatogenic disturbance or midpiece deformities.

Actins↗

PubMed2006

Human testis specific protein 1 expression in human spermatogenesis and involvement in the pathogenesis of male infertility.

Human testis specific protein 1 (TPX1) exists in the cytomembrane and cytoplasm of spermatogenic cells from pachytene spermatocytes to elongated spermtids, including pachytene spermatocytes, round spermtids and elongated spermtids. It is localized in the connecting piece, the flagellum, and the acrosome of mature human spermatozoa. The protein level and localization of TPX1 were altered in patients with spermatogenic arrest and in infertile men with oligoasthenoteratospermia syndrome.

Adult↗

PubMed2006

Involvement of ALF in human spermatogenesis and male infertility.

We conducted this study to explore functions of TF II Aalpha/beta-like factor (ALF) during human spermatogenesis, and the relationship of its expression levels with male infertility. The RT-PCR and Western blot analyses illustrated that ALF was highly expressed in adult testis. Immunohistochemistry and immunoflurescence showed that ALF is located in the spermatid nuclei and in the annulus of spermatozoa. Further, to reveal whether ALF is related to male infertility, we performed the same experiments in infertility patients. The changes in the expression levels of ALF in the male infertility samples lead us to believe that ALF may function in spermatogenesis, especially in spermiogenesis. We also detected the ALF DNA methylation level by real-time methylation-specific PCR (MSP) both in testes of adult, fetal and infertile patient. The differential expression level of ALF gene in different types of testes was regulated by DNA methylation. Our research identified ALF as a human spermatogenesis related gene, the abnormal expression of ALF might be the partial cause for human infertility.

Gene Expression Profiling↗

PubMed2005

Molecular cloning, identification and characteristics of a novel isoform of carbamyl phosphate synthetase I in human testis.

A gene coding a novel isoform of carbamyl phosphate synthetase I (CPS1) was cloned from a human testicular library. As shown by cDNA microarray hybridization, this gene was expressed at a higher level in human adult testes than in fetal testes. The full length of its cDNA was 3831 bp, with a 3149 bp open reading frame, encoding a 1050-amino-acid protein. The cDNA sequence was deposited in the GenBank (AY317138). Sequence analysis showed that it was homologous to the human CPS1 gene. The putative protein contained functional domains composing the intact large subunit of carbamoyl phosphate synthetase, thus indicated it has the capability of arginine biosynthesis. A multiple tissue expression profile showed high expression of this gene in human testis, suggesting the novel alternative splicing form of CPS1 may be correlated with human spermatogenesis.

Adult↗

PubMed2005

Effects of diet-induced hypercholesterolemia on testosterone-regulated protein expression in mice liver.

We report here testosterone deficiency in diet-induced hypercholesterolemic mice. We attempted to compare the liver protein profiles between hypercholesterolemic and normal mice by using the technology of proteomics. Protein extractions from mice livers were separated by two-dimensional electrophoresis and the gels were analysed with image analysis software 2D Elite 4.0. The differentially expressed proteins were identified primarily by comparing with reference gel images in the SWISS 2DPAGE database and then confirmed by peptide mass fingerprinting. Sixteen differentially expressed protein spots (>2-fold) were detected and 8 of which were identified as major urinary proteins, carbonic anhydrase III, and glutathione S-transferase P2, which are known to be regulated by androgens. The expression of these three proteins was statistically lower in the livers of hypercholesterolemic mice. Meanwhile, the testosterone levels in serum, testis, and liver were lower in hypercholesterolemic mice than those in normal mice, when human chorionic gonadotrophin was injected intramuscularly. These results suggest a testosterone deficiency in diet-induced hypercholesterolemic mice.

Animals↗

PubMed2005

Identification of a novel substrate for tyrosine kinase in human testes.

Identification of genes specifically expressed in adult and fetal testes is important in furthering our understanding of testis development and function. In this study, a novel human specific transcript, designated NYD-SP10, was identified by hybridization of adult and fetal human testis probes with a human cDNA microarray. NYD-SP10 (GenBank Accession no. AF332192) was expressed at a higher level in adult testes than in fetal testes. Bioinformatic analysis illustrated NYD-SP10 is a splice variant of regulatory factor X4, while it is lack of RFX DNA-binding domain which binds to the X box of MHC class II genes. Most telling of all, NYD-SP10 uniquely possesses a tyrosine kinase phosphorylation site. Expression profiles demonstrated NYD-SP10 is specifically and strongly expressed in human adult testes and ejaculated spermatozoa. Taken together, these results suggest that NYD-SP10 is a novel testis-specific gene and it is possibly a novel substrate for tyrosine kinase and involved in the function of human spermatozoa, especially during capacitation.

Adult↗

PubMed2005

Cloning and characterization of a novel intronless lactate dehydrogenase gene in human testis.

Using cDNA microarray hybridization from a human testicular cDNA library, one gene named lactate dehydrogenase A-like gene (LDHL, also known as LDHL6B) was cloned. LDHL exhibited 3.8-fold difference at expression level between adult and fetal human testes. The full cDNA length of LDHL is 1680 bp and had a 1145 bp open reading frame, which encoded a 41.9 kDa protein of 381 amino acids. Sequence analysis showed that LDHL harbors all the domains (one lactate/malate dehydrogenase, NAD binding domain and one lactate/malate dehydrogenase, alpha/beta C-terminal domain) in lactate dehydrogenase gene family. Blasting human genome database localized LDHL to human chromosome 15q22.2 and it was an intronless gene. Results of multiple-tissue PCR and real-time PCR showed that LDHL expressed mainly in testis and its mRNA abundance was testis development-related. In summary, LDHL is believed to be involved in testis development and spermatogenesis.

Amino Acid Sequence↗

PubMed2005

SMYD3-NY, a novel SMYD3 mRNA transcript variant, may have a role in human spermatogenesis.

Identification of genes specifically expressed in adult and fetal testis is important to further our understanding of testis development and function. In this study, a novel SMYD3 transcript variant, termed SMYD3-NY (GenBank Accession No. AY186742), was identified by hybridization of adult and fetal human testis cDNA probes with a human cDNA microarray. SMYD3-NY transcript was expressed at 2.3-fold higher levels in adult human testis than in fetal testis, with a low expression level in human spermatozoa. Bioinformatical analysis showed that SMYD3-NY protein has the SET domain that is involved in histone methyltransferase (HTMase) activity. Southern blotting showed that SMYD3-NY is distributed in several tissues, including testis. In summary, SMYD3-NY is a novel transcript variant of the SMYD3 gene, and SMYD3-NY protein may influence transcriptional regulation during spermatogenesis via HTMase activity.

Adult↗

PubMed2004

A spermatogenesis-related gene expression profile in human spermatozoa and its potential clinical applications.

Spermatogenesis is an essential stage in the human reproductive process. In a previously study aiming to determine which genes might be involved in spermatogenesis, we compared the gene expression profiles of adult and fetal testes by hybridizing cDNA probes prepared from adult and fetal testes to membranes dotted with gene clones derived from a commercial human testis library. We identified 266 differentially expressed genes that showed higher expression levels in adult testes, indicating their potential roles in spermatogenesis. In the present study, we applied the same cDNA microarray technique to the analysis of gene expression in the spermatozoa of normal fertile men and found 149 genes that were expressed at higher levels in adult testis. A further study of five sperm motility-related genes selected from this profile by real-time PCR revealed that there was significant difference in the expression levels of two genes ( TPX-1, testis-specific protein 1 and LDHC, lactate dehydrogenase C, transcript variant 1) between normal ( n=29) and motility impaired ( n=24) semen samples, indicating that these genes are involved in sperm function. Our results demonstrated that spermatogenesis-related gene profiling could help to assess sperm quality in humans, and further study of these genes will help us to elucidate the mechanisms involved in spermatogenesis and diseases relating to human infertility.

A Kinase Anchor Proteins↗

PubMed2004

Expression of a novel DnaJA1 alternative splicing in human testis and sperm.

Using cDNA microarray hybridization from a human testicular cDNA library, one gene exhibiting threefold difference at expression level between adult and embryo human testes was named nDnaJA1 (a new alternative isoform of human DnaJA1 which was also named HDJ2/Hsdj/dj2, a human HSP40 homologue), which was believed to be involved in testis development and spermatogenesis. Multiple tissue polymerase chain reaction (PCR) results showed that nDnaJA1 expressed highly in testis and lung but low in thymus, prostate, colon and liver. The results of the other members of DnaJA1 family (GenBank accession numbers: D13388 and BC008182) showed that they were widely expressed. D13388 and BC008182 were highly expressed in sperm while nDnaJA1 was faintly expressed by reverse transcriptase PCR. Protein motif analysis of nDnaJA1 sequence revealed motifs of DnaJ. nDnaJA1 was considered as type I DnaJ like the other members of DnaJA1 family.

Alternative Splicing↗

PubMed2004

A Gene Encoding Sialic-Acid-Specific 9-O-Acetylesterase Found in Human Adult Testis.

Using differential display RT-PCR, we identified a gene of 2750 bp from human adult testis, named H-Lse, which encoded a putative protein of 523 amino acids and molecular weight of 58 kd with structural characteristics similar to that of mouse lysosome sialic-acid-specific 9-O-acetylesterase. Northern blot analysis showed a widespread distribution of H-Lse in various human tissues with high expression in the testis, prostate, and colon. In situ hybridization results showed that while H-Lse was not detected in embryonic testis, positive signals were found in spermatocytes but not spermatogonia in adult testis of human. The subcellular localization of H-Lse was visualized by green fluorescent protein (GFP) fused to the amino terminus of H-Lse, showing compartmentalization of H-Lse in large dense-core vesicles, presumably lysosomes, in the cytoplasm. The developmentally regulated and spermatogenic stage-specific expression of H-Lse suggests its possible involvement in the development of the testis and/or differentiation of germ cells.

Journal Article↗

PubMed2004

Cloning and expression of a novel CREB mRNA splice variant in human testis.

Identification of genes specifically expressed in adult and fetal testis is important in furthering our understanding of testis development and function. In this study, a novel human transcript, designated human testis cAMP-responsive element-binding protein (htCREB), was identified by hybridization of adult and fetal human testis cDNA probes with a human cDNA microarray containing 9216 clones. The htCREB transcript (GenBank Accession no. AY347527) was expressed at 2.35-fold higher levels in adult human testes than in fetal testes. Sequence and ntBLAST analyses against the human genome database indicated that htCREB was a novel splice variant of human CREB. RT-PCR-based tissue distribution experiments demonstrated that the htCREB transcript was highly expressed in adult human testis and in healthy sperm, but not in testes from patients with Sertoli cell-only syndrome. Taken together, these results suggest that the htCREB transcript is chiefly expressed in germ cells and is most likely involved in spermatogenesis.

Alternative Splicing↗

PubMed2004

The molecular characteristics of polycystic ovary syndrome (PCOS) ovary defined by human ovary cDNA microarray.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders; it is characterized by polycystic ovaries, hyperandrogenism and chronic anovulation. To obtain a global view of those genes that might be involved in the development of this complex clinical disorder, we used recently developed cDNA microarray technology to compare differential gene expressions between normal human ovary and ovaries from PCOS patients. A total of 9216 clones randomly selected from a commercial human ovary cDNA library were screened. Among them, 290 clones showed differential expressions, including 119 known genes and 100 known or unknown expressed sequence tags (ESTs). Among 119 known genes, 88 were upregulated and 31 downregulated in the PCOS ovary, as compared with normal human ovary. These differentially expressed genes are involved in various biologic functions, such as cell division/apoptosis, regulation of gene expression and metabolism, reflecting the complexity of clinical manifestations of PCOS. The molecular characteristics established from our study will further our understanding of the pathogenesis of PCOS and help us to identify new targets for further studies and for the development of new therapeutic interventions.

Base Sequence↗

PubMed2004

[Effects of reproductive hormones on spermatogenesis].

Spermatogenesis, a continuous course of cell proliferation and differentiation, depends on reproductive hormones. FSH and LH-induced T are the main hormones regulating spermatogensis. Intratesticular T is one of the key factors in maintaining spermatogenesis, while FSH is just as important for origination and maintenance of normal spermatogenesis. Sertoli cells are the pivot of hormonal regulation. Interestingly, these reproductive hormones also regulate sperm cell apoptosis spermatogenesis. Further studies on the hormonal regulation of spermatogenesis provide a base for the development of safe and recoverable contraceptives for males.

Androgens↗

PubMed2004

[Phospholipase C and reproduction].

Phospholipase C (PLC) is a key enzyme in phosphatidyl inositol turnover during signal transduction. The 12 mammalian PLC isozymes identified to date can be divided into five subtypes, beta-type, gamma-type, delta-type, epsilon-type and zeta-type, with extensive difference in structure, regulatory mechanism and tissue distribution. PLC plays important roles not only in sperm acrosome reaction but also in egg activation. The present studies are reviewed on the structure, regulation and function of PLC, especially its function in male reproduction, including triggering Ca2+ oscillations in eggs to activate the eggs and helping embryo development. And the prospect of the clinical application of PLC is discussed.

Acrosome Reaction↗