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961.
The polymorphism in follicle stimulating hormone beta (FSHB) subunit gene was detected by PCR-SSCP and PCR-RFLP methods in 780 does from four goat breeds including Boer, Matou, Black and Boer-Matou crossbred (BM). The associations of FSHB genotypes with litter size (LS), litter weight at birth (LWB) and gestation length (GL) as well as superovulation performances were analyzed in relatively lower-prolific Boer and higher-prolific Matou breeds. A 1514 bp linear DNA sequence of goat FSHB gene covering the complete 3 exons was cloned by four pairs of primer. A new mutation (A2645G, GenBank Accession no: S64745) locating in exon 3 causing an amino acid change from glutamine (Gln) to arginine (Arg) at residue 115 was identified, which resulted in three genotypes named AA, AB and BB. The three genotypes were detected in the four studied goat breeds. The higher-prolific Matou breed had the highest frequency of genotype AA. Association analysis showed that Boer and Matou does with AA genotype have the largest LS both in average and in parities from first to fourth (P < 0.05). Furthermore, Boer does with AA genotype had the heaviest LWB compared to other two genotypes (P < 0.05). Matou does with AA genotype have more numbers of ova harvested, large follicles and corpus lutea on ovaries after superovulation than those with BB genotype (P < 0.05). Therefore, these results suggest that the FSHB gene is a candidate gene that affects reproduction traits in goats.  相似文献   
962.
Neo1p from Saccharomyces cerevisiae is an essential P-type ATPase and potential aminophospholipid translocase (flippase) in the Drs2p family. We have previously implicated Drs2p in protein transport steps in the late secretory pathway requiring ADP-ribosylation factor (ARF) and clathrin. Here, we present evidence that epitope-tagged Neo1p localizes to the endoplasmic reticulum (ER) and Golgi complex and is required for a retrograde transport pathway between these organelles. Using conditional alleles of NEO1, we find that loss of Neo1p function causes cargo-specific defects in anterograde protein transport early in the secretory pathway and perturbs glycosylation in the Golgi complex. Rer1-GFP, a protein that cycles between the ER and Golgi complex in COPI and COPII vesicles, is mislocalized to the vacuole in neo1-ts at the nonpermissive temperature. These phenotypes suggest that the anterograde protein transport defect is a secondary consequence of a defect in a COPI-dependent retrograde pathway. We propose that loss of lipid asymmetry in the cis Golgi perturbs retrograde protein transport to the ER.  相似文献   
963.
964.
Small heat shock proteins (sHSPs) are the most diverse but also the most poorly known family of molecular chaperones, and they play essential roles in various biological processes. The striped stem borer, Chilo suppressalis (Insecta: Lepidoptera: Pyralidae), is one of the most serious pests of rice, causing extensive damage and yield loss. In this study, we isolated and characterized five members of the sHSPs family—Cshsp19.8, Cshsp21.4, Cshsp21.5, Cshsp21.7a, and Cshsp21.7b—from C. suppressalis. The cDNAs of these genes encoded proteins of 177, 187, 191, 191, and 191 amino acids with isoelectric points of 7.0, 5.6, 6.1, 6.3, and 6.3, respectively. While Cshsp19.8, Cshsp21.5, and Cshsp21.7b had no introns, Cshsp21.4 and Cshsp21.7a contained one and two introns, respectively. Structural analysis indicated that all five Cshsps possessed conserved arginine and a V/IXI/V motif, which is related to hydrophobic characteristics of sHSPs. The five heat shock proteins can be classified into two main groups: an orthologous type (Cshsp21.4 and Cshsp21.7a) and a species-specific type (Cshsp19.8, Cshsp21.5, and Cshsp21.7b). Real-time quantitative PCR analyses revealed that Cshsp19.8, Cshsp21.5, Cshsp21.7a, and Cshsp21.7b all exhibited their highest expression levels within Malpighian tubules or the hindgut, while such levels were found in the head for Cshsp21.4. The expression of Csshsps at different developmental stages revealed that the mRNA levels of Cshsp19.8, Cshsp21.4, Cshsp21.5, and Cshsp21.7b peaked in adults, whereas the highest level of Cshsp21.7a was observed in first instar larvae. Cshsp19.8 and Cshsp21.7b were both upregulated dramatically by heat and cold, and Cshsp21.5 could be induced by cold stress. Neither Cshsp21.4 nor Cshsp21.7a responded to heat or cold. These results demonstrated that different Csshsps play distinctive roles in the regulation of the physiological activities in C. suppressalis.  相似文献   
965.
Lu Liu  Bao-Zhen Hua 《Tissue & cell》2017,49(5):622-631
Bittacidae and Panorpidae are the two largest families in Mecoptera. The larvae of Bittacidae are different from those of Panorpidae in external morphology and habits, and have an interesting habit of spraying the body surface with soil through the anus. However, it remains unknown to date whether the larval midguts are different in structure between the two families. Here the ultrastructure of the larval midguts of the hangingfly Bittacus planus Cheng and the scorpionfly Neopanorpa longiprocessa Hua & Chou were compared using light, scanning, and transmission electron microscopy. The midguts of both species are simple tubes of single layered epithelia with digestive and regenerative cells but without diverticula. The basal plasma membrane of epithelial cells exhibits infolding in B. planus, but is closely apposed to its basal lamina in N. longiprocessa. Lymph spaces are present between adjacent epithelial cells in B. planus, but are absent in N. longiprocessa. The regenerative cells are scattered among the digestive cells in B. planus, but are aggregated in N. longiprocessa. The longitudinal muscle bands are compact in B. planus, but are sparse in N. longiprocessa. The compact longitudinal muscle bands are likely associated with their soil-spraying habit in Bittacidae.  相似文献   
966.
The purpose of the present study was to determine the effect of angiotensin II (A-II) on membrane expression of Na+/H+ exchange isoforms NHE3 and NHE2 in the rat renal cortex. A-II (500 ng/kg per min) was chronically infused into the Sprague-Dawley rats by miniosmotic pump for 7 days. Arterial pressure and circulating plasma A-II level were significantly increased in A-II rats as compared to control rats. pH-dependent uptake of 22Na+ study in the presence of 50 μM HOE-694 revealed that Na+ uptake mediated by NHE3 was increased ∼88% in the brush border membrane from renal cortex of A-II-treated rats. Western blotting showed that A-II increased NHE3 immunoreactive protein levels in the brush border membrane of the proximal tubules by 31%. Northern blotting revealed that A-II increased NHE3 mRNA abundance in the renal cortex by 42%. A-II treatment did not alter brush border NHE2 protein abundance in the renal proximal tubules. In conclusion, chronic A-II treatment increases NHE3-mediated Na+ uptake by stimulating NHE3 mRNA and protein content.  相似文献   
967.
968.
969.
周仕顺  王洪  朱华 《广西植物》2005,25(2):104-104
在对中国科学院西双版纳热带植物园标本馆植物标本的鉴定清理工作中,发现中国新记录植物2种,兹报道如下,供有关部门和研究者参考。  相似文献   
970.
悬浮培养红豆杉细胞活力及存活率与生长周期的关系   总被引:8,自引:0,他引:8  
刘华 《生物学杂志》2002,18(1):19-20
用TTC法制定红豆杉细胞活力,用中性红测细胞存活率,探讨生长周期中细胞活力及存活率的变化规律。结果显示延迟期细胞活力最强,对数生长期活力较低,稳定期活力最低;而细胞存活率在整个周期中基本保持在70%-80%。  相似文献   
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