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31.
哺乳动物配子发生的基因表达调控包括编码基因的阶段特异性表达调控及非编码基因的转录和转录后水平调控。微小RNA(microRNA, miRNA)作为一类小的非编码RNA, 通过识别靶基因非翻译区的结合位点, 导致mRNA降解或者蛋白质翻译抑制, 从而在转录后水平发挥调控作用。近年来, miRNA在哺乳动物生殖活动中的作用逐渐被揭示, 越来越多的研究表明, miRNA在哺乳动物精子发生、精子成熟、卵母细胞成熟、卵泡发育及早期胚胎发育等过程中都发挥着重要的调节作用, 其可通过调节支持细胞的增殖和凋亡或精原细胞、精母细胞及精细胞的细胞周期进程, 在精子发生的不同阶段发挥间接或直接调控作用, 也可通过调节卵母细胞、卵丘细胞以及颗粒细胞的增殖、凋亡、激素合成和细胞间作用, 对卵母细胞的发育和成熟过程进行调控。作者主要介绍了在哺乳动物配子发生过程中, miRNA的细胞和阶段特异性表达及其对靶基因的调节作用, 以期为深入研究哺乳动物配子发生的调控机制提供参考。 相似文献
32.
Kikumi OGIHARA Ken ONDA Reiichiro SATO Yuko NAYA Hideharu OCHIAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):85-88
L-type amino acid transporter
1 (LAT1), the first isotype of amino acid transport system L, transports aromatic and
branched amino acids pivotal for fundamental cellular activities such cellular growth and
proliferation. LAT1 expression was high only in the brain in contrast to its limited
distribution and low level of expression in normal tissues. We found potent LAT1
expression in canine caput epididymis by quantitative RT-PCR and Western blotting
analysis. Immnuno-histochemical examination revealed observable LAT1 in microvillous
epithelial cells. 相似文献
33.
Takahiro AYA Yukiko TOMIOKA Takashi TAKEUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1144
The effect of lactoferrin (LF) on embryo development was investigated by using lipopolysaccharide (LPS)-treated mouse sperm. For the development rate of the 2-cell stage embryo, the embryo derived from LPS- and LF-treated sperm showed similar survival rate to the control embryo. On day 12 after the embryo transfer into the recipient, the frequent abnormality was observed in the embryo derived from LPS-treated sperm, and the abnormality was tended to be inhibited in the embryo derived from LPS- and LF-treated sperm. These results imply that LF treatment on sperm contaminated with bacteria may facilitate the embryo development, which contribute to the improvement of infertility. 相似文献
34.
为明确双组分系统FlrBC在嗜水气单胞菌极生鞭毛合成、生物被膜形成及致病机制中的作用,通过同源重组法,以嗜水气单胞菌ZYAH72为野生菌株构建双组分系统FlrBC缺失株ΔflrB和ΔflrC,比较不同菌株鞭毛合成及游动性、生物被膜形成、胞外多糖分泌、细胞黏附以及抗全血杀伤能力差异。结果显示:与野生株相比,ΔflrB和ΔflrC仍能形成极生鞭毛,细菌游动能力无显著差异;而结晶紫染色发现ΔflrB和ΔflrC相较于野生株的生物被膜形成能力分别下降了27.2%和22.3%;刚果红检测结果显示,与野生株相比,ΔflrB和ΔflrC的胞外多糖分泌分别下降了18.4%和14.2%;实时荧光定量PCR的结果显示,flrB和flrC的缺失不同程度抑制了鞭毛合成、生物被膜相关通路基因的表达;与草鱼肾细胞共孵育后,ΔflrB和ΔflrC的细胞黏附率与野生株相比分别下降了23.2%和18.2%;全血杀伤实验结果显示,ΔflrB和ΔflrC抗全血杀伤能力均显著减弱。以上结果表明,双组分系统FlrBC不是嗜水气单胞菌极生鞭毛形成所必需,但在细菌鞭毛形成组装和生物被膜形成中发挥调控作用,并且影响嗜水气单胞菌致病性... 相似文献
35.
盐度对西施舌精子活力及受精孵化的影响 总被引:2,自引:0,他引:2
在水温23.5℃下,采用显微观察的方法研究了不同盐度梯度下西施舌精子活力的差异,并探讨了盐度对西施舌受精率及受精卵孵化率的影响。研究表明,西施舌精子在盐度28中呈现最好的活力,快速活动的精子占92.95%;在盐度28~35中,受精率都高达98%以上,而分别在盐度10和45中未发现受精卵;盐度25~30的孵化率都达80%以上,盐度分别为15和40下的受精卵未继续发育而死亡。因此,适宜西施舌受精的最佳盐度范围为25~30。 相似文献
36.
Jacky Cosson 《Aquaculture International》2004,12(1):69-85
This review presents actual knowledge about energetic, ionic, osmotic and gaseous control of fish sperm motility and its duration. Right after they are activated, fish spermatozoa of most species swim for a short period of time, in the range of one to several minutes. What determines the activation process? Is it due to the new ionic, gaseous and/or osmotic environment? Why is the duration of motility so short? Is it resulting from a fast exhaustion of energy stores (ATP, ADP, AMP, PCr) combined with the above-mentioned ionic/osmotic stress leading to morphological alterations? The motility criteria (flagellar beat frequency, head displacement velocity, flagellar waves morphology, etc.) used to characterize fish sperm movement and sperm flagella will be described. Most parameters change very rapidly during the brief motility period of fish sperm. Then will be considered the main environmental factors, ionic and/or osmotic signals, responsible of the activation of fish sperm motility. Then the metabolic compounds involved in cell energetics will be considered as their concentrations also rapidly change during the motility phase. An additional feature will then be discussed concerning the mechanisms by which fish sperm cell can be revived for a second motility round at the end of the first motility period. A model is proposed to explain how external osmolarity can control internal ionic composition, the latter being the key factor controlling flagellar activity. 相似文献
37.
38.
In vitro effects of Musa x paradisiaca extracts on four developmental stages of Haemonchus contortus
C. Marie-Magdeleine L. Udino L. Philibert B. Bocage H. Archimede 《Research in veterinary science》2014
This study was carried out to evaluate the in vitro effect of Musa x paradisiaca stem and leaf against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and/or dichloromethane) of Musa x paradisiaca stem and leaf were tested in vitro on four developmental stages of H. contortus using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI) and adult worm motility assay (AWM). The highly significant (P < 0.0001) ability to stop larval development (inhibition >67% for each extract) and the negative effect of the dichloromethane extract of leaf on adult worm motility (43% of inhibition of motility after 24 h of incubation) compared to the negative controls, suggest anthelmintic properties of Musa x paradisiaca stem and leaf against H. contortus. The active principles responsible for the activity could be secondary metabolites such as terpenoid and flavonoid compounds present in the leaf and stem of the plant. 相似文献
39.
Allison M. Kiser Steven P. Brinsko Charles C. Love Dickson D. Varner Kendrick Sudderth Terry L. Blanchard 《Journal of Equine Veterinary Science》2014
This study evaluated measures of sperm quality in relation to fertility achieved with fresh semen or semen cooled and stored. Semen from 1 stallion was collected and processed to provide 3 treatments: group 1 received fresh semen; group 2 received cooled semen containing 50% seminal plasma (SP) stored for 4 days; and group 3 received cooled semen containing 50% SP stored for 1 day, then centrifuged and resuspended in fresh extender containing 10% SP on days 1 to 3. Inseminates were evaluated for sperm motion characteristics and the percentage of sperm with intact membranes (SMI). Mares (n = 34) in estrus were treated with an ovulation-inducing drug and inseminated with 100 million membrane-intact sperm on the following day. Pregnancy status was determined via transrectal ultrasonography 2 weeks after ovulation. The mean percentage of SMI was higher in group 1 (81%, initial) than in group 2 (74%, day 4) or group 3 (74%, day 4) (P < .05). The median percentages of total sperm motility differed among the groups (77%, 5%, 59% for groups 1, 2, and 3 respectively; P < .05). Median values for the percentages of progressively motile sperm and curvilinear velocity for group 1 (55%, 216 μm/s) and 3 (37%, 186 μm/s) were higher than for group 2 (1%, 73 μm/s) (P < .05). Pregnancy rates did not differ among groups (5 of 11, 45% in group 1; 5 of 11, 45% in group 2; and 7 of 12, 58%, in group 3; P = .77). These data suggest that, at least for this stallion, sperm membrane integrity may be a more valuable means of assessing potential fertility of cooled-stored semen than sperm motion characteristics. 相似文献