人源类溶菌酶蛋白6在男性生殖系统中的表达

目的:检测人源类溶菌酶蛋白6(LYZL6)在男性生殖系统中的表达情况,以揭示其可能的生理功能。方法:将整合LYZL6编码基因的毕赤酵母菌株进行高密度培养,甲醇诱导表达后甲壳素亲和色谱纯化。采用双层琼脂平板扩散法观察重组LYZL6的杀菌活性。以纯化的重组蛋白为免疫原制备兔抗LYZL6多克隆抗体,ELISA检测抗体效价。通过Western印迹检测LYZL6蛋白在人各组织及精液中的分布,并采用免疫组化法确认LYZL6在人睾丸中的表达情况。结果:在低p H条件下重组LYZL6对溶壁微球菌杀菌活性较高。以重组LYZL6为免疫原制备的抗体具有高效价,Western印迹检测表明LYZL6仅在睾丸和附睾中表达,且睾丸表达水平较高。在人精子蛋白提取物中检测到了LYZL6,精浆中并未检测到明显蛋白条带。免疫组化检测显示在睾丸组织中,LYZL6定位于晚期精母细胞及圆形精子细胞。结论:在低p H条件下,重组LYZL6具有较强的溶解细菌细胞壁的能力;LYZL6被睾丸上皮分泌后结合于精子上,提示LYZL6有可能在精卵融合过程的某个环节发挥作用。     

人源类溶菌酶蛋白4的多克隆抗体制备及其表达分析

目的:以原核表达的人源类溶菌酶蛋白4(LYZL4)为免疫原制备多克隆抗体,检测LYZL4在睾丸组织中的定位,为阐明其生理功能提供依据。方法:将LYZL4编码基因克隆于原核表达载体pET32a,IPTG诱导重组LYZL4(r LYZL4)表达。分别使用Ni-NTA树脂和甲壳素亲和层析纯化rLYZL4,采用双层琼脂平板扩散法检测杀菌活性。以Ni-NTA树脂纯化产物为免疫原制备兔抗rLYZL4多克隆抗体,通过ELISA测定抗体效价,Western印迹检测抗体特异性后,检测LYZL4蛋白在人体各组织的分布及其在精子和精浆中存在情况,免疫组化确认LYZL4在人睾丸组织中的定位。结果:原核表达系统可有效表达rLYZL4,其对溶壁微球菌及大肠杆菌无杀灭活性。制备的兔抗rLYZL4多克隆抗体具有很高的效价和特异性,在睾丸、附睾及人精子蛋白提取物中可检测到LYZL4存在,在生精小管中,LYZL4定位于圆形精子细胞及长形精子细胞的顶体上。结论:本研究成功以原核表达的rLYZL4制备了该蛋白的多克隆抗体,确认LYZL4在睾丸和附睾有表达,并定位于精子顶体上,提示其可能与顶体结构或功能相关。     

人源类溶菌酶蛋白4在受精过程中的作用及酶学性质研究

目的:对人源类溶菌酶蛋白4(LYZL4)在受精过程中的作用和重组蛋白的酶学性质进行研究,从而揭示LYZL4的生理功能。方法:细胞免疫荧光法检测LYZL4在精子细胞上的亚细胞定位,RT-PCR分析精子表面LYZL4的来源,通过精子穿透试验分析LYZL4在受精过程中的作用。构建真核重组表达载体p PIC9K-LYZL4,转化毕赤酵母GS115菌株后,甲醇诱导表达;甲壳素亲和层析和凝胶过滤层析从发酵上清中纯化重组LYZL4蛋白(rLYZL4),通过Western印迹进行验证。ELISA测定rLYZL4的透明质酸结合能力,分光光度法测定rLYZL4的胞壁质酶活性、透明质酸酶活性和自由基清除能力。结果:LYZL4免疫荧光定位于成熟精子头部的顶体膜上,RTPCR检测表明精子表面的LYZL4蛋白来源于睾丸和附睾的分泌,兔抗LYZL4多克隆抗体可明显抑制精卵结合。毕赤酵母表达系统成功表达了rLYZL4,酶活性分析显示rLYZL4无胞壁质酶和透明质酸酶活性,但能够结合透明质酸,并具有较强的自由基清除能力。结论:LYZL4由睾丸和附睾分泌后定位于成熟精子头部的顶体膜上,可在精卵结合过程中发挥作用,其还能够结合透明质酸并清除自由基,提示LYZL4可能作为一种多功能分子在精子保护及精卵结合过程中发挥作用。     

Ccdc70基因在小鼠睾丸精子发生过程中的表达特征

目的:探讨Ccdc70(Coiled-coil domain containing 70)基因在小鼠睾丸中的表达特征并分析其在生精过程中的潜在功能。方法:经表达谱芯片筛选出小鼠睾丸特异性基因Ccdc70,通过RT-PCR、real-time PCR、Western印迹及免疫组化检测Ccdc70基因在成年小鼠睾丸中表达特征,并对该蛋白做相关的生物信息学分析。结果:RT-PCR、real-time PCR和Western印迹结果表明Ccdc70基因在小鼠睾丸中高表达,在附睾中低表达;免疫组化结果表明Ccdc70蛋白在睾丸中主要表达于小鼠精母细胞和圆形精子胞质,在附睾中主要表达在附睾管上皮细胞。生物信息学分析显示该蛋白存在一个CCDC结构域,并在哺乳动物进化过程中高度保守。结论:Ccdc70为小鼠睾丸高表达基因,且主要表达于精母细胞、圆形精子及附睾管上皮细胞,提示其可能参与调控小鼠精子发生过程及附睾精子的进一步成熟。     

【原创论文】小鼠杀菌渗透增强性蛋白起源于睾丸及附睾表达并定位于精子中

杀菌渗透增强性蛋白（BPI）是具有抗革兰氏阴性菌活性的内源性杀菌蛋白。在本研究中,我们通过自行制备的多克隆抗体,检测了BPI蛋白在小鼠出生后睾丸及附睾组织中的表达,以及在附睾精子头部的亚细胞定位。实验结果表明,睾丸和附睾均独立表达BPI基因。在附睾中,自起始段至尾部,BPI蛋白的表达水平递减,并逐步特异性富集于亮细胞的胞质中。在顶体反应前的顶体基质内可见BPI蛋白,应起源于睾丸表达;顶体反应后,可见BPI蛋白分布于整个精子头部质膜表面,尤其是赤道板区域,可能有睾丸或附睾表达的两种起源。我们的研究结果提示,BPI蛋白可能参与顶体反应前后精子质膜结构的调控,并参与后续的精卵融合过程。     

去泛素化酶24基因在小鼠睾丸精子发生过程中的表达特征

目的:研究去泛素化酶24(USP24)基因在小鼠睾丸精子发生过程中的表达特征,初步探讨其在生精过程中的作用。方法:通过实时荧光定量PCR(qPCR)和免疫荧光等方法检测USP24在不同周龄野生型小鼠睾丸组织以及成年雄激素受体敲除(ARKO)小鼠睾丸中的表达特征;采用双荧光素酶报告基因实验检测USP24启动子转录活性。结果:qPCR和免疫荧光结果表明,USP24基因在出生1周时表达水平较低,3周时急剧升高,随后维持在相似水平至第8周;USP24主要定位于支持细胞和生精细胞的细胞质;与野生型相比,USP24在ARKO小鼠睾丸表达降低;性成熟小鼠睾丸中,USP24定位于成熟精子头部后端及中部。双荧光素酶报告基因实验结果显示,睾酮刺激后USP24启动子的转录活性升高。结论:USP24基因的表达水平的升高与小鼠的性发育相关,且其蛋白在小鼠成熟精子上表达。USP24是受雄激素受体(AR)调控的靶基因。USP24可能参与调控小鼠的精子发生过程。     

精子超活化结构蛋白——Catsper表达特性研究

目的:Catsper是精子特有的一种阳离子通道蛋白,对于精子超活化有重要的调节作用,为进一步了解其表达特性,本文主要研究其组织特异性表达及表达规律。方法:运用RT-PCR和免疫组织化学方法分析Catsper在2~8周龄昆明小鼠睾丸、附睾等8种组织中的表达情况,在精子上的精确定位以及随发育阶段变化表达量的变化。结果:Catsper特异性地表达于睾丸和附睾组织上;主要定位于精子尾部的主段;Catsper的表达量受到发育阶段的调控,该蛋白表达量随个体发育周龄的增长而呈增加的趋势,于3周龄开始检测到它的表达,随后表达量显著增加至6周龄,以后逐渐增长至一个平台期。结论:小鼠的Catsper基因特异性地表达于睾丸和附睾上,并且主要位于精子尾部的主段,其表达量与小鼠的发育阶段有密切的关系。     

Lyzl6基因在小鼠中的表达及其生物信息学分析

目的分析Lyzl6基因在小鼠中的表达特点.方法本研究通过RT-PCR实验明确Lyzl6基因在9、15、18、21、28、35d和6月龄小鼠睾丸中的表达变化及Lyzl6基因在成年小鼠各组织表达特点.采用多种生物信息学方法对该基因进行生物信息学分析.结果 RT-PCR结果显示,Lyzl6基因在小鼠21d龄及之前的睾丸中没有表达,28d睾丸中开始持续高表达.Lyzl6基因在14种小鼠组织中呈现睾丸显著高表达.经生物信息学分析,Lyzl6蛋白属于典型的C型溶菌酶,是一种分泌蛋白,其蛋白的信号肽剪切位点在第19~20个氨基酸之间.小鼠和人Lyzl6蛋白氨基酸序列有高度相似性和同源性,显示该基因在哺乳动物中高度保守.结论Lyzl6基因为小鼠睾丸年龄依赖性表达基因,在小鼠睾丸中高表达,显示其可能在生精过程发挥重要作用.     

雄激素对小鼠和大鼠的支持细胞和附睾细胞中Pem基因同源域的调节作用

雄激素对睾丸和附睾的功能至关重要，在垂体切除后的大鼠和基因突变的性腺发育不全小鼠的睾丸中，睾酮维持着精子的产生。在一定程度上，支持细胞与胚细胞密切接触，在雄激素的作用下，使胚细胞经过有丝分裂、减数分裂和精子成熟，从而促进精子的产生。在附睾中，雄激素可以调节沿管腔排列的体细胞的生长和分化。雄激素可以调节附睾中粘附蛋白的合成、管腔内液体中蛋白的分泌，以及附睾上皮层内离子和小分子的转运，从而控制了精子成熟的微环境。人们虽已明白睾丸中的精子发生和附睾中的精子成熟是依赖雄激素的过程，但是有关这些生物过程的…     

雄激素/雄激素受体对小鼠附睾Caveolin-1表达调控机制的研究

目的:探讨雄激素和雄激素受体(AR)对小鼠附睾Caveolin-1表达的调控机制。方法:通过搜索前期染色体免疫共沉淀-测序(ChIP-seq)实验得到的小鼠附睾AR结合位点的数据库,寻找Caveolin-1基因相关联的AR结合位点。分别取正常小鼠、睾丸阉割小鼠以及睾丸阉割后补充外源雄激素的小鼠的附睾组织,一方面,抽提总RNA,利用逆转录PCR以及逆转录荧光定量PCR检测Caveolin-1基因的mRNA表达水平;另一方面,利用AR抗体进行染色体免疫共沉淀(ChIP),采用ChIP-PCR以及ChIP-qPCR的方法,检测Caveolin-1基因相关联的AR结合位点在体内与AR的结合情况。结果:从小鼠附睾AR结合位点的数据库中找到两个Caveolin-1相关联的AR结合位点,均位于第二内含子区域。睾丸阉割后,Caveolin-1基因的表达显著升高(P<0.05),表达量是对照组的(1.8±0.17)倍;两个AR结合位点的富集倍数分别由正常状态下的(13.5±1.47)倍和(10.5±1.03)倍降至(1.05±0.17)倍和(1.4±0.14)倍(P<0.01)。补充雄激素后,Caveolin-1基因的表达又降至正常水平(P<0.05),为正常对照组的(1.03±0.06)倍。两个AR结合位点的富集倍数则分别升至(16.4±2.6)倍和(10.0±0.92)倍(P<0.01)。结论:Caveolin-1在小鼠附睾内是AR的一个直接靶基因,其表达受雄激素的负调控。该研究为理解雄激素/AR在小鼠附睾内的调控网络提供了新的视角。     

急性热应激对性成熟雄性小鼠睾丸、附睾、输精管中热休克蛋白70表达的影响

目的:探讨急性热应激对性成熟雄性小鼠睾丸、附睾、输精管中热休克蛋白70(heat shock protein 70,HSP70)表达的影响。方法:将32只8周龄雄性小白鼠随机均分为4组,饲养7d后,进行热应激处理,温度控制在(39±0.5)℃,时间分别为0.5、1和3h。应激后立即采血,分离血清测定谷草转氨酶(GOT)含量。一侧附睾制备精子悬液,用于计算精子密度和顶体畸形率;另一侧附睾、睾丸、输精管用于免疫组化研究。结果:应激后,小鼠体重、睾丸系数、顶体畸形率变化不显著(P>0.05),附睾系数和精子密度有不同程度的下降,GOT含量急剧升高(P<0.01)。随着应激时间的延长,小鼠精子密度呈递减趋势,顶体畸形率呈上升趋势。应激时间最短的0.5h组小鼠体重、睾丸系数、附睾系数的降幅反而最大。免疫组化法观察发现,HSP70在性成熟小鼠睾丸、附睾、输精管中均有表达。正常状态下,HSP70在睾丸组织间质细胞中少量表达,应激后分布于间质细胞核,此外在精母细胞核与精子细胞核中也有大量分布;附睾中HSP70主要分布于主细胞质,基细胞和亮细胞中没有表达,应激后附睾体的纤毛细胞中也发现大量棕色颗粒;输精管中HSP70主要定位在基细胞质,主细胞中不表达。随着应激时间的延长,HSP70在睾丸、附睾中的表达量明显升高,而在输精管中的增幅不明显。结论:急性热应激对性成熟雄性小鼠的生殖系统造成了损伤;HSP70在睾丸、附睾、输精管中的表达与定位具有区域特异性和细胞特异性,提示其可能参与精子的发生与成熟;HSP70在应激状态下表达量大幅上升的作用可能在于保护细胞免受高热损伤。     

Localization of Hsp60 and Grp78 in the human testis, epididymis and mature spermatozoa

Molecular chaperones of the heat shock proteins (HSP) family are important in numerous cellular processes. In this study, the expression of Hsp60 and Grp78 proteins was investigated in the male reproductive tract. The cellular distribution of Hsp60 and Grp78 proteins was analysed in the human testis and epididymis by immunohistochemical approaches. DNA microarray technology was used to analyse HSP60 and GRP78 gene expression along human epididymis. The cellular localization of these chaperone proteins in ejaculated spermatozoa was investigated by indirect immunofluorescence and by Western blot following sperm sub-cellular fractionation. In the human testis, Hsp60 was detected in spermatogonia, whereas a strong Grp78 staining was observed in spermatocytes and round spermatids. Grp78 protein was also observed in the epididymal epithelium, whereas no Hsp60 staining was observed in this organ by immunohistochemistry. The presence of both Hsp60 and Grp78 RNA in human epididymis was confirmed by microarrays. In ejaculated spermatozoa, Hsp60 was localized in the mid-piece, whereas Grp78 was detected in the neck region. These results indicate that in addition to being expressed in human testis spermatogenic cells, both Hsp60 and Grp78 proteins persist in ejaculated spermatozoa. These findings are in agreement with the involvement of Hsp60 and Grp78 during spermatogenesis and in sperm functions such as fertilization.     

CatSper基因家族在人和小鼠组织中的表达特征

目的研究CatSper基因家族在人和小鼠组织中的分布特点。方法将不同发育阶段的小鼠睾丸组织cDNA与Affymetrix全基因组芯片探针进行杂交,筛选出差异表达基因CatSper基因家族。RT—PCR验证差异表达基因在不同发育阶段的小鼠睾丸组织的表达特征,及其在人和小鼠不同组织中的分布。结果基因芯片分析发现CatSper1、CatSper2和CatSper3在小鼠睾丸的表达呈阶段特异性。RT-PCR结果表明该基因家族在睾丸的表达丰度明显高于其它组织;CatSper1和CatSper4在人体睾丸组织中特异性表达。结论CatSper基因家族在人和小鼠中呈现睾丸特异性表达或高表达,可能在精子发生中发挥重要功能。     

Expression of Cdv-iR gene in mouse epididymis as revealed by in situ hybridization

We have previously studied mouse Cdv (carnitine deficiency-associated gene expressed in ventricle)-1 related gene Cdv-1IR and its human counterpart CDV-1R, and revealed that mouse Cdv-1R was predominantly expressed in testis by multiple tissue northern analysis. To further localize the Cdv-1R mRNA in mouse testis and epididymis tissue, in situ hybridization study was reported in this article. In the adult mice, the Cdv-1R expression was intensively found in the epithelial cells of the caput and corpus epididymis, whereas it was moderately detected in the initial segment, and weakly in the cauda epididymis. In the seminiferous tubles of the testis, no obvious hybridization signals were observed above the background level. This Cdv-1R region-specific expression pattern in the epididimis suggests Cdv-1R may play an important role in sperm maturation. Moreover, considering the Cdv-1R has a similar expression distribution in epididymis to the OCTN2, it would appear that Cdv-1R might be involved in the carnitine pathway in the epididimis.     

小鼠BPI体内外抗溶脲脲原体生长的实验研究

目的:通过体内外实验,检测小鼠杀菌渗透性增强蛋白(bactericidal/permeability-increasing protein,BPI)是否对溶脲脲原体(Ureaplasma urealyticum,UU)的生长有抑制作用。方法:UU与Bac-to-Bac系统真核表达的BPI共孵育0.5~2h后培养16~20h,通过颜色变化单位(CCU)观察BPI体外抗UU生长的效果;膀胱注射UU,逆行感染小鼠生殖道,通过观察睾丸和附睾BPI的mRNA和BPI蛋白表达的变化来检测BPI体内抗UU的效果。结果:UU与BPI孵育0.5h,在蛋白量40μg时,BPI可抑制UU生长;随孵育蛋白量的增加,BPI对UU抑制效应增加。UU与BPI孵育2h,BPI对UU的抑制效应无明显变化。UU逆行感染成功的小鼠睾丸和附睾的BPI在基因和蛋白水平均显著提高(P0.01)。结论:小鼠BPI在体内外均对溶脲脲原体的生长有抑制作用。     

IL-10 is highly expressed in the cryptorchid cryptepididymal epithelium: a probable mechanism preventing immune responses against autoantigenic spermatozoa in the epididymal tubule

The expression of several immunoregulatory adhesion proteins and cytokines was studied in the normal epididymis, cryptorchid cryptepididymis, the epididymis of oestrogen-treated mice and the epididymis of non-obese diabetic (NOD) mice at the protein level to see which of these immunoregulatory proteins may be involved in lymphocyte regulation in the normal or pathological epididymis and if cytokine balance in this organ is on the cellular or humoral side. The aim of the study was to characterize the immunological microenvironment of the epididymis to explain the survival of the autoantigenic spermatozoa in this site. In the 6-week-old BALB/c or NOD mouse epididymis there were some CD18 and CD44 expressing cells in the interstitial tissue. There were no differences between these strains in the expression of the studied antigens, except that some CD4 positive cells were present in the interstitial tissue of BALB/c mice. In the cryptorchid cryptepididymis CD4, CD8, CD18, CD44, CD54 and CD106 expressing cells were occasionally present in the connective tissue surrounding the epididymal tubule. In the epididymis of the oestrogen-treated mice these antigens were not expressed. In the cryptorchid cryptepididymis the epithelial cells expressed IL-10 highly and the myoid peritubular cells IL-6. The present results suggest that the epididymal epithelial IL-10 suppressing TH0, TH1 and TH2 immune responses may be involved in the protection of autoantigenic spermatozoa from immune destruction.     

Expression and distribution of OCTN2 in mouse epididymis and its association with obstructive azoospermia in juvenile visceral steatosis mice

AIM: L-carnitine, an essential cofactor for mitochondrial, beta-oxidation of long-chain fatty acids, is known to play important roles in sperm maturation and metabolism when spermatozoa pass and acquire motility in the epididymis. We reported that obstructive azoospermia occurred in the epididymis in the juvenile visceral steatosis (JVS) mice, which are OCTN2 dysfunction mice caused by mutations in the gene encoding OCTN2, have been used for animal models of primary systemic carnitine deficiency. The aim of present study is to investigate the expression of OCTN2 protein in the mouse epididymis and its relation between the localization of OCTN2 and obstructive azoospermia in JVS mice as animal models for human male infertility. METHODS: Animals used in this study were wild-type (C57BL/6 J) mice (n = 4) and JVS mice (n = 4). We made a specific polyclonal antibody against OCTN2 and examined immunohistochemically the localization of OCTN2 in the mouse epididymis. RESULTS: OCTN2 was localized on the apical membrane of the principal cells of distal corpus and cauda epididymides. Immunocytochemistry demonstrated that OCTN2 was localized on the surface of microvillus upon the principal cells. In JVS mice, immunoreactivity started in a region immediately distal to where the sperm obstruction occurred. CONCLUSIONS: Our results suggest that OCTN2 functions as a carnitine transporter between the epithelium and the lumen in distal corpus and cauda epididymides and provides a clue as to why obstructive azoospermia is induced in distal parts of epididymis.