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TSUYOSHI OHIRA HIDEKAZU KATAYAMA KATSUMI AIDA HIROMICHI NAGASAWA 《Fisheries Science》2003,69(1):95-100
ABSTRACT: Until now, six crustacean hyperglycemic hormones (CHH) designated Pej-SGP-I, -II, -III, -V, -VI and -VII have been characterized in the kuruma prawn Penaeus japonicus . All CHH consist of 72 amino acid residues and have an amidated carboxyl (C)-terminus. In the present study, we expressed Pej-SGP-III in methylotrophic yeast Pichia pastoris in order to obtain a large quantity of recombinant CHH possessing biological activity. A cDNA encoding Pej-SGP-III that had been previously cloned was processed by polymerase chain reaction (PCR) and the resulting product was ligated into an expression vector. Pichia pastoris was transformed with this vector after which a recombinant Pej-SGP-III was expressed having an additional amino acid residue (glycine) at the C-terminus (rPej-SGP-III-Gly), a form considered to be a putative precursor of this hormone. rPej-SGP-III-Gly secreted into the culture medium was purified by reversed-phase HPLC, and amidated using a peptidylglycine alpha-amidating enzyme. The amidated rPej-SGP-III (rPej-SGP-III) showed hyperglycemic activity in in vivo bioassay almost comparable to that of the natural Pej-SGP-III. rPej-SGP-III thus obtained will be a useful tool not only for its physiological study but also for the determination of its 3-D structure. 相似文献
3.
糯米糍荔枝果实内源激素与落果的关系 总被引:1,自引:0,他引:1
以糯米糍荔枝生理落果期的田间调查和胚胎发育研究为基础,探讨了内源激素与生理落果的关系.结果表明,糯米糍生理落果高峰的主要原因是:第1次因授粉受精不良导致的生长促进类激素尤其是CTK水平过低;第2次与胚乳为胚的发育所利用而消失、IAA和GAs急剧降低有关;第3次与胚的败育造成CTK、GAs和IAA的全面下降有关;第4次发生在假种皮(果肉)迅速生长期,与种皮和假种皮ABA升至高水平有关.此外,还探讨了ABA /(IAA+GAs+CTK)与生理落果的相关性,以及胚囊、珠被和假种皮等果实内部组分内源激素的变化特点. 相似文献
4.
20%多效唑·甲哌 FEE7 微乳剂防止小麦倒伏和增产机理研究 总被引:1,自引:0,他引:1
冬小麦二棱期喷施植物生长调节剂20%多效唑·甲哌鎓微乳剂375 mL/hm2,可以显著抑制茎秆基部节间伸长,增加各节间充实度,其中赤霉素(Gas)和生长素(IAA)降低,可显著增强小麦抗倒伏能力和降低田间倒伏率.处理还协调了穗数、穗粒数和粒重的关系,增产幅度6.2%~28.6%.增产原因可能在于促进籽粒灌浆强,增加籽粒中内源Gas、IAA、细胞分裂素(CTKs)的水平,增强了籽粒库活性,同时促进茎叶中干物质向籽粒运转. 相似文献
5.
Evaluation of Serum Symmetric Dimethylarginine Concentration as a Marker for Masked Chronic Kidney Disease in Cats With Hyperthyroidism 下载免费PDF全文
6.
Histological and immunohistochemical evaluation of granulosa cells during different stages of folliculogenesis in bovine ovaries 下载免费PDF全文
APP Teh UZ Izzati K Mori N Fuke T Hirai G Kitahara R Yamaguchi 《Reproduction in domestic animals》2018,53(3):569-581
Bovine granulosa cells (GC) vary in their morphological aspect during different stages of folliculogenesis. In this study, 10 morphologically normal bovine ovaries were collected to study the structural aspects of different stages of GC using intermediate filament protein antibodies including cytokeratin AE1/AE3 (AE1/AE3), vimentin, nectin‐4 and desmin. Hormonal immunolocalization was assessed using the immunomarkers anti‐Müllerian hormone (AMH) and inhibin alpha. In addition, tumour markers and proliferation markers using c‐erbB‐2 oncoprotein and proliferating cell nuclear antigen, respectively, were investigated. The immunolabelling of AE1/AE3 in GC was strongest in the early follicle stage and gradually decreased when reaching the Graafian follicle stage. Its immunolabelling increased again as the stage progressed from stage I to stage III. The immunolabelling of inhibin alpha was inversely proportional to that of AE1/AE3 in the developing ovarian follicles as their immunolabelling is opposite to each other during folliculogenesis. AMH was immunopositive in almost all GC stages in different intensities and percentages, except for some negative staining in the atretic IV follicles. The atretic IV follicle is a unique type of atretic follicle that shows Call‐Exner body formation, which was mainly found in older cows in this study. The distinct patterns of immunoreactivity for various types of immunomarkers in the different GC stages will play an important role in diagnostic assistance of various follicle conditions, including cystic ovaries and GC tumours. 相似文献
7.
采用PCR-RFLP-ApaⅠ方法检测高坡猪GH基因-119~ 486 bp片段的多态性,探讨了不同基因型对其部分生产性能的影响。结果表明:产生2个等位基因A(449 bp)和B(316 133 bp),其频率分别为0.54和0.46;3种基因型:AA、AB和BB,其频率分别为0.26、0.56和0.18;除6月龄腹围和背膘厚外,其余指标值均以BB基因型最高,AA基因型的6月龄腹围和瘦肉率与BB基因型相比差异显著(P<0.05),其他指标在各基因型间差异均不显著(P>0.05)。表明,A可能是小型猪的有利等位基因,B则可能是大型猪的有利等位基因。 相似文献
8.
核桃幼树内源激素与生长势的关系 总被引:5,自引:0,他引:5
激素在果树生长发育过程中起着重要调控作用,基因通过激素控制植株高矮(曾骧,1992).对苹果(Maluspumila)、李(Prunus salicina)、桃(Prunus persica)等果树内源激素与生长势的关系已有一些报道(王丽琴等,2002;周怀军等,2002;孙艳香等,2001),但在核桃上有关研究尚少.本试验以核桃(Juglans regia)不同品种的嫁接植株及实生苗为试材,探讨内源激素与树体生长势的关系,为选择核桃矮化砧木提供理论依据. 相似文献
9.
This paper studied on the way of Coleus blumei, the leaf was chosen as explants and was inoculated on 1/2 MS medium with different combinations of 6-benzyladenine (6-BA), α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA). The optimal conditions of callus induction from explants were achieved on the medium containing 6-BA (2.0 mg· L^-1) and NAA (1.0 mg· L^-1). Shoot tips were induced on the medium containing 6-BA (4.0 mg·L^-1) and NAA (0.5 mg·L^-1). The same media conditions were found suitable for shoot multiplication, we multiplied shoots rooted best on 1/2 MS medium supplemented with IBA (0.1 mg·L^-1). 相似文献
10.
提高牦母牛繁殖性能的研究 总被引:5,自引:4,他引:1
张君 《青海畜牧兽医杂志》2007,37(3):8-10
采用不同剂量生殖激素处理3.5岁的青年牦母牛,结果发情率提高5.84和23.26个百分点,繁殖率分别提高34.69和41.21个百分点。采用不同剂量生殖激素处理和怀孕牦母牛围产期补饲的措施,促进产后成年牦母牛发情配种,结果发情率分别提高42.42,54.67和37.51个百分点,繁殖率提高43.93,48.48和20.10个百分点。生殖激素处理和围产期补饲对提高牦牛繁殖性能有较大的促进作用,高剂量生殖激素的促进效果较明显。 相似文献