A Dominant Locus, qBSC-1, Controls β Subunit Content of Seed Storage Protein in Soybean(Glycine max(L.) Merri.)

Soybean seed storage protein is one of the most important plant vegetable proteins, and β subunit is of great significance to enhance soybean protein quality and processing property. F2 segregated population and residual heterozygous lines（RHL） derived from the cross between Yangyandou（low level of β subunit） and Zhonghuang 13（normal level of β subunit） were used for mapping of β subunit content. Our results showed that β subunit content was controlled by a single dominant locus, qBSC-1（β subunit content）, which was mapped to a region of 11.9 cM on chromosome 20 in F2 population of 85 individuals. This region was narrowed down to 2.5 cM between BARCSOYSSR_20_0997 and BARCSOYSSR_20_0910 in RHL with a larger population size of 246 individuals. There were 48 predicted genes within qBSC-1 region based on the reference genome（Glyma 1.0, Williams 82）, including the two copies of β subunit coding gene CG4. An InDel marker developed from a thymine（TT） insertion in one copy of CG4 promoter region in Yangyandou cosegregrated with BARCSOYSSR_20_0975 within qBSC-1 region, suggesting that this InDel marker maybe useful for marker-assisted selection（MAS）.

Gene Cloning and Tissue-Specific Expression of G Protein β Subunit in Microplitis mediator (Hymenoptera: Braconidae)

A gene encoding a novel G protein β subunit of β1 subclass, GβMmed was isolated from Microplitis mediator （Hymenoptera： Braconidae）. The full-length sequence of GβMmed is 1 119 bp, the cDNA contains a 1 023 bp open reading frame that encodes a protein with 340 amino acids, and the predicted molecular weight of GβMmed is 37.23 kDa and isoelectric point is 5.86. By the quantitative real-time RT-PCR method, the tissue-specific expression and quantitative changes in the developmental expression profile of GβMmed were detected. It was found that GβMmed was abundantly expressed in M. mediator antennae, head （without antennae）, thorax, abdomen, legs and the wings, and especially at high levels in abdomen. In antennae, expression varied through 1st day before emergence to 5-d-old adults, and had equal expression levels detected in females and males in total. In head, GβMmed expresses while initially high in females, and have another peaked in stage 4 and 1st day, in males showed a peak of GβMmed expression prior to emergence and relatively low levels after emergence. In female abdomen GβMmed expression levels have two peaks in stage 1 and the 5th d, but just have one peak in male abdomen in stage 1. In all other tissues expression was low and stable.

G-protein β subunit AGB1 positively regulates salt stress tolerance in Arabidopsis

The heterotrimeric GTP-binding proteins（G-proteins） in eukaryotes consisted of α, β and γ subunits and are important in molecular signaling by interacting with G-protein-coupled receptors（GPCR）, on which to transduce signaling into the cytoplast through appropriate downstream effectors. However, downstream effectors regulated by the G-proteins in plants are currently not well defined. In this study, the transcripts of AGB1, a G protein β subunit gene in Arabidopsis were found to be down-regulated by cold and heat, but up-regulated by high salt stress treatment. AGB1 mutant（agb1-2） was more sensitive to high salt stress than wild-type（WT）. Compared with WT, the cotyledon greening rates, fresh weight, root length, seedling germination rates and survival rates decreased more rapidly in agb1-2 along with increasing concentrations of Na Cl in normal（MS） medium. Physiological characteristic analysis showed that compared to WT, the contents of chlorophyll, relative proline accumulation and peroxidase（POD） were reduced, whereas the malonaldehyde（MDA） content and concentration ratio of Na＋/K＋ were increased in agb1-2 under salt stress condition. Further studies on the expression of several stress inducible genes associated with above physiological processes were investigated, and the results revealed that the expressions of genes related to proline biosynthesis, oxidative stress response, Na＋ homeostasis, stress- and ABAresponses were lower in agb1-2 than in WT, suggesting that those genes are possible downstream genes of AGB1 and that their changed expression plays an important role in determining phenotypic and physiologic traits in agb1-2. Taken together, these findings indicate that AGB1 positively regulates salt tolerance in Arabidopsis through its modulation of genes transcription related to proline biosynthesis, oxidative stress, ion homeostasis, stress- and ABA-responses.

Involvement of sulfur assimilation in the low β subunit content of soybean seed storage protein revealed by comparative transcriptome analysis

The β subunit of soybean [Glycine max (L.) Merr.] seed storage protein is of great significance in sulfur-containing amino acid balance and soybean processing properties. The objective of this study was to elucidate the relationship between the β subunit and sulfur-containing amino acid composition, and the potential regulatory mechanism. The β subunit was independently accumulated in comparison with other major subunits (α/α′, acidic, basic, and A3) during seed filling, and a low level of β subunit content (BSC) was formed during the accumulation process. In low-BSC mature seeds, crude protein, oil content, and fatty acid composition were not changed, but sulfur-containing amino acids (Cys + Met) in the low- BSC seeds increased significantly (by 31.5%), suggesting that an internal regulatory mechanism within seed might be responsible for the rebalance of seed protein composition and that sulfur assimilation might be deeply involved in β subunit accumulation. Transcriptomic analysis revealed that genes involved in anabolism of cysteine, methionine, and glutathione were up-regulated but those involved in the catabolism of these compounds were down-regulated, suggesting a relationship between the elevation of methionine and glutathione and low BSC. Our study sheds light on seed composition in low BSC lines and on the potential molecular regulatory mechanism of β subunit accumulation, broadening our understanding of soybean seed protein synthesis and its regulation.

Comparison of cleavage activity in vitro between two ribozymes targeted against different sites of PDGF receptor β subunit

Objective: To compare the cleavage activity of ribozymes directed against 2 sites of PDGF receptorP subunit cDNA gene in vitro. Methods: The 608 bp fragment of PDGF receptor β subunit cDNA was clonedinto T-vector under the control of T7 promoter, named pPDGFR-β. Two ribozymes were designed to cleavethe CUU sequence at codon 45 and codon 252 of PDGF receptor β subunit mRNA respectively. These 2 ham-merhead ribozyme genes were cloned into vector PI. 5 between 5' -cis ribozyme and 3' -cis ribozyme to gener-ate the plasmids of pRZ1 and pRZ2. The pPDGFR-β, pRZl and pRZ2 were linearized and then transcribedwith T7 promoter in vitro. Results: The RZ1 showed high cleavage activity in vitro, but the RZ2 showed nocleavage activity under the same condition. Conclusion: The cleavage site selection is an important factor in-fluencing the cleavage activities of ribozymes.

ATP Synthase β-subunit Abnormality in Pancreas Islets of Rats with Polycystic Ovary Syndrome and Type 2 Diabetes Mellitus

This study investigated the abnormal expression of ATP synthase β-subunit（ATPsyn-β） in pancreas islets of rat model of polycystic ovary syndrome（PCOS） with type 2 diabetes mellitus（T2DM）,and the secretion function changes after up-regulation of ATP5 b.Sixty female SD rats were divided into three groups randomly and equally.The rat model of PCOS with T2 DM was established by free access to the high-carbohydrate/high-fat diet,subcutaneous injections of DHEA,and a single injection of streptozotocin.The pancreas was removed for the detection of the ATPsyn-β expression by immunohistochemical staining,Western blotting and reverse transcription-PCR（RT-PCR）.The pancreas islets of the rats were cultured,isolated with collagenase Ⅴ and purified by gradient centrifugation,and the insulin secretion after treatment with different glucose concentrations was tested.Lentivirus ATP5 b was successfully constructed with the vector of GV208 and transfected into the pancreas islets for the over-expression of ATPsyn-β.The insulin secretion and intracellular ATP content were determined after transfection of the PCOS-T2 DM pancreas islets with Lenti-ATP5 b.The results showed that the expression of ATPsyn-β protein and m RNA was significantly decreased in the pancreas of PCOS-T2 DM rats.The ATP content in the pancreas islets was greatly increased and the insulin secretion was improved after the up-regulation of ATPsyn-β in the pancreas islets transfected with lenti-ATP5 b.These results indicated that for PCOS,the ATPsyn-β might be one of the key factors for the attack of T2 DM.

The Study on Immuno-response and Antisera Properties of Recombinant β-subunit of Human Chorionic Gonadotropin in C57 Black Mouse

In this study, the immuno-response of recombinant hCG-β and natural hCGβ was comparatively investigated by using Freund's adjuvant. The results showed that, the properties and merits of the antibodies elicited by both kinds of hCG-β were similar. The antisera had high affinity for binding with hCG (Kαγβ≈5.86×108/mol/L, Kαβ≈8.18×108/mol/L), and were found to be effective in inhibiting the binding of 125I-hCG to receptors in rat testes. Results also indicated that, similar to the antisera induced by natural hCG-β, the recombinant hCG-β induced antisera had capacity of neutralizing the biological activities of hCG. Recombinant hCG-β could be used as an immunogen for contraceptive vaccine.

不同7S亚基组份的大豆蛋白纳米颗粒包埋β-胡萝卜素Pickering乳液研究

为探究不同7S亚基组份大豆蛋白纳米颗粒对包埋β-胡萝卜素Pickering乳液的影响,本研究以野生型大豆(Wild)、α亚基缺失型大豆(α-lack)、α′亚基缺失型大豆(α′-lack)和(α+α′)亚基缺失型大豆[(α+α′)-lack]作为试验原料,提取大豆分离蛋白(SPI),通过扫描电镜、粒径和表面疏水性对比热诱导前后蛋白的变化,利用蛋白纳米颗粒为乳化剂制备包埋β-胡萝卜素Pickering乳液,通过测定包埋β-胡萝卜素Wild-NPPEs、α-lack-NPPEs、α′-lack-NPPEs和(α+α′)-lack-NPPEs的粒径、抗氧化能力(DPPH自由基清除率)、β-胡萝卜素的保留率、模拟消化后的游离脂肪酸释放率和生物可及性等指标,探索α、α′亚基对包埋β-胡萝卜素的影响。结果表明:通过热诱导可以制备不同亚基组份的蛋白纳米颗粒,α′亚基对包埋β-胡萝卜素Pickering乳液的稳定性有影响,在4℃或25℃下经过30 d贮藏后,α′-lack-NPPEs的β-胡萝卜素的最终保留率超过70%,且抗氧化活性最高;通过体外模拟胃肠消化试验,α′-lack-NPPEs乳液液滴的界面面积比较大,结合游离脂肪酸释放率结果发现,随着聚合度降低、油滴表面积增加,水解率提高,使β-胡萝卜素在胶束相中的保留含量提高,从而其生物可及性增加。综上,α′-lack-NPs更适合用于制备较稳定的包埋β-胡萝卜素Pickering乳液。

CDK5RAP1通过Wnt/β-Catenin信号通路调控结直肠癌发生和进展的研究

目的探讨周期素依赖性激酶5激活结合蛋白1(CDK5RAP1)通过Wnt/β-连环蛋白(β-Catenin)信号通路对结直肠癌(CRC)发生和进展的影响。方法选取2020年6月至2022年9月在贵阳市第一人民医院被首诊为CRC的72例患者的CRC组织和癌旁组织,检测组织中CDK5RAP1的表达水平。选取人CRC细胞系HCT-116、SW480、HT29、SW620、Caco-2及人正常结直肠上皮细胞系NCM460,检测各细胞中CDK5RAP1的表达水平。分别将si-NC和si-CDK5RAP1转染至HCT-116细胞中,分别将pc-NC和pc-CDK5RAP1转染至SW480细胞中,将SW480细胞分为SW480-CON组(正常培养细胞)、SW480-pc-NC组(阴性对照细胞)、SW480-pc-CDK5RAP1组(CDK5RAP1过表达细胞)和SW480-HLY78组(SW480-pc-CDK5RAP1+20μmol/L Wnt激活剂HLY78),将HCT-116细胞分为HCT-116-CON组(正常培养细胞)、HCT-116-si-NC组(阴性对照细胞)、HCT-116-si-CDK5RAP1组(CDK5RAP1低表达细胞)和HCT-116-HLY78组(HCT-116-si-CDK5RAP1+20μmol/L HLY78)。检测各组CRC细胞中CDK5RAP1的表达水平、CRC细胞存活率(增殖能力)、克隆、侵袭、迁移情况,以及CRC细胞成球率(细胞干性)。检测各组CRC细胞中β-Catenin、Axin1、c-Myc、CD133、CD44、SOX2蛋白的表达水平。选取18只BALB/C裸鼠随机分为CON组、si-NC组和si-CDK5RAP1组,每组6只,分别在各组裸鼠右前肢腋下注射对应的HCT-116细胞悬液,5周后处死裸鼠,剥离移植瘤并称重比较。结果CRC组织及细胞中CDK5RAP1的表达水平均显著高于癌旁组织和人正常结直肠上皮细胞(P均<0.05),且CDK5RAP1在HCT-116细胞中表达水平最高,在SW480细胞中表达水平最低,故分别使用HCT-116细胞和SW480细胞构建CDK5RAP1敲低和过表达的慢病毒载体转染细胞株。与SW480-CON组和SW480-pc-NC组比较,SW480-pc-CDK5RAP1组细胞的CDK5RAP1表达水平、细胞存活率、细胞克隆率、细胞划痕愈合率、细胞侵袭数量、细胞成球率及β-Catenin、c-Myc、CD133、CD44、SOX2蛋白表达水平均显著升高,Axin1蛋白表达水平显著降低(P均<0.05)。与HCT-116-CON组和HCT-116-si-NC组比较,HCT-116-si-CDK5RAP1组细胞的CDK5RAP1表达水平、细胞存活率、细胞克隆率、细胞划痕愈合率、细胞侵袭数量、细胞成球率及β-Catenin、c-Myc、CD133、CD44、SOX2蛋白表达水平均显著降低,Axin1蛋白表达水平显著升高(P均<0.05)。HLY78可促进过表达CDK5RAP1的SW80细胞的增殖、迁移、侵袭及干性,也可逆转CDK5RAP1低表达对HCT-116细胞增殖、迁移、侵袭和干性的抑制。si-CDK5RAP1组裸鼠移植瘤的质量较CON组和si-NC组均显著降低(P均<0.05),体积也显著缩小。结论CDK5RAP1靶向Wnt/β-catenin信号通路参与CRC的发生和进展。敲低CDK5RAP1表达可通过Wnt/β-catenin信号通路抑制CRC细胞的增殖、迁移、侵袭和干性。

猪FSHβ亚基基因结构区Alu序列插入突变的研究

通过聚合酶链式反应 (PCR)对中国华北型优良地方猪种莱芜猪及杜里猪、长白猪的卵泡刺激素 (FSH) β亚基基因结构区插入片段进行扩增 ,并对 0 .5kb扩增产物进行克隆和测序。序列分析表明 ,在已发表的猪FSHβ亚基基因全序列的 +80 9与 +810碱基之间 ,莱芜猪、杜里猪和长白猪分别存在一个长度为 2 75、2 77和 2 74bp的插入片段 ,插入片段末端的poly(A)分别为 17、19和 16个腺苷酸 ,均显著短于高产猪种太湖猪 (2 92bp和 32个腺苷酸 )。对FSHβ亚基基因插入片段进行BamHⅠ多态性分析 ,发现本研究所检测样品中不存在BamHⅠ多态性。插入片段中存在一个RNA聚合酶Ⅲ启动子及AluⅠ内切酶识别位点 ,所以该片段可能为Alu成分。因RNA聚合酶Ⅲ这种有功能的内部启动子能够转录相邻的染色体序列 ,该插入片段可能影响FSHβ亚基基因或其他基因的表达调控。把FSHβ亚基基因作为控制猪产仔数主效基因的候选基因与产仔数进行连锁分析 ,证明FSHβ基因座位在莱芜猪种中与控制猪产仔数的主效基因紧密连锁 ,优势基因AA纯合子比BB纯合子母猪平均每胎多产仔 1.2头。因不同品种猪插入序列的主要差异是末端的poly(A)长短不同 ,推测该插入片段末端的poly(A)结构亦可能影响猪的产仔数。

中国大豆蛋白亚基构成分析与缺失部分亚基的特异大豆品种的筛选

大豆蛋白亚基组成的不同直接影响大豆蛋白的加工特性与营养特性。本研究利用SDS-PAGE电泳分析大豆蛋白质组成并提出了便捷的样品预处理方法。对1 624个中国大豆栽培品种的分析结果表明,构成大豆蛋白的主要亚基均有一定变异,同时,结合Western blot分析,首次在中国大豆栽培品种中发现了β-伴大豆球蛋白的β-亚基缺失的大豆品种,为大豆蛋白质的品质改良育种和加工理论研究提供了重要的材料。

重组人蛋白激酶CK2β亚基cDNA的克隆与测序

蛋白激酶ＣＫ２是一种存在的信使非依赖性丝／苏氨酸蛋白激酶．它是由两个催化亚基（α或α′）和两个调节亚基（β）组成的不均一四聚体．用反转录ＰＣＲ从ＨＬ－６０细胞中获得了人蛋白激酶ＣＫ２β亚基编码区ｃＤＮＡ，将ＮｄｅⅠ／ＨｉｎｄⅢ双酶切ＰＣＲ产物连接到表达载体ｐＴ７－７的ＮｄｅⅠ／ＨｉｎｄⅢ双酶切位点中．转化感受态细菌ＤＨ５α获得转化子，阳性筛选率为７２％．限制性酶切分析结果表明，插入片段和重组质粒的大小与理论推测值相符．随机挑选４个阳性质粒测定其插入片段ＤＮＡ序列，结果显示有２个含有正确插入的人蛋白激酶ＣＫ２βｃＤＮＡ，命名为ｐＴＣＫＢ．其余２个克隆分别存在１个和２个点突变，即在其编码区ｃｏｎｄｏｎ１４８的ＴＣＡ→ＴＴＡ，结果Ｓｅｒ→Ｌｅｕ；另一个则在Ｃｏｎｄｏｎ１４３ＧＴＧ→ＡＴＧ，Ｖａｌ→Ｍｅｔ；Ｃｏｎｄｏｎ１７０ＧＴＧ→ＧＣＧ，Ｖａｌ→Ａｌａ．重组质粒（ｐＴＣＫＢ）克隆的成功，将为在原核细胞中表达蛋白激酶ＣＫ２β亚基以及利用ＣＫ２βｃＤＮＡ作为探针进行深入研究打下基础．

人绒毛膜促性腺激素α、β亚基cDNA的筛选与序列分析

构建３周龄人胚ｃＤＮＡ 文库，用［α－３２Ｐ］ｄＣＴＰ标记的一链ｃＤＮＡ 为探针从中筛选高度表达的克隆子并测序，得到人绒毛膜促性腺激素（ＨＣＧ）的α和β亚基ｃＤＮＡ 克隆，序列同源性分析表明：α亚基编码区的ｃＤＮＡ 序列与已报道的完全同源，β亚基编码区第３０位碱基Ｇ→Ａ，该碱基的改变不引起氨基酸的改变．另外，在α和β亚基非编码区发现有多处碱基的改变．

猪FSH-β位点对猪繁殖性状的影响

采用 PCR- SSCP技术对猪 FSH- β亚基基因的多态性进行了研究。结果表明 ,基因型分布与品种极显著相关 (P<0 .0 0 5 ) ;除大梅 F1 以外 ,所研究群体的 FSH-β PCR- SSCP位点均处于遗传平衡状态 ;在头胎中 ,G等位基因可以显著提高产仔数和产活仔数 ,加性效应分别为 1.2 0 0头 /窝、1.345头 /窝 (P<0 .0 5 ) ;在经产胎次 ,GG基因型母猪的产仔数和产活仔数显著高于 HH基因型 (P<0 .0 5 ) ,每拷贝 G等位基因可以控制 0 .6 18头 /窝的产仔数和 0 .834头 /窝的产活仔数 ;GG基因型母猪乳头数多 (P<0 .0 5 ) ,加性效应为 1.4 2 9个 ,而后代乳头数没有显著的差异 ,可以确定猪乳头数主要受自身基因型决定 ,且具有一定母本效应 ;GG型后代平均初生重比 HH型低 ,GH型的育成率显著比 HH型高(P<0 .0 5 ) ;GG基因型母猪的年产仔窝数显著低于 GH型 (P<0 .0 5 ) ;GG基因型的断奶到发情间隔比 GH基因型显著短 (P<0 .0 5 ) ,GH基因型的断奶到配种间隔显著比 HH基因型短 (P<0 .0 5 )。

团头鲂促性腺激素β亚基cDNA的克隆和序列分析

本研究利用RT-PCR和RACE克隆了团头鲂(Megalobrama amblycephala)脑下垂体中两种促性腺激素β亚基(GtHIβ和GtHIIβ)cDNA序列,并对其进行了结构和系统进化分析。团头鲂GtHIβ亚基cDNA全长567碱基对(bp),5’端非翻译区26bp;3’端非翻译区148bp;开放阅读框(ORF)393bp,其编码含有130个氨基酸的蛋白质,包括由108个氨基酸组成的成熟肽以及22个氨基酸组成的信号肽。GtHII亚基cDNA全长564bp,5’端非翻译区43bp;3’端非翻译区95bp;ORF426bp,其编码含有141个氨基酸的蛋白质,包括由117个氨基酸组成的成熟肽以及24个氨基酸组成的信号肽。团头鲂GtHIβ亚基氨基酸序列与青鱼(Mylopharyngodon piceus)等15种鱼类相比较,相似性为90%—31%,与湖蛙(RanaRidibunda)等5种四足类的相似性为38%—21%;GtHII亚基与青鱼等15种鱼类相比较,其相似性为95%—41%,与湖蛙等5种四足类的相似性为49%—36%,团头鲂GtHIβ和GtHII亚基与鲤科鱼类的相似性最高,显示出较为亲近的进化关系。另外,团头鲂GtHIβ和GtHIIβ亚基含有12个保守的半胱氨酸残基和1个N糖基化位点。

9种Na^＋通道mRNA在5个不同发育阶段大鼠16种组织中表达及变化趋势

电压-门控Na^＋通道由1个可单独发挥作用的α亚单位和2～4个起辅助作用的β亚单位构成,在可兴奋细胞动作电位的产生及传导等过程中起重要作用.采用RT-PCR法对5个不同发育阶段（P1、P9、P40、P80、P120）Wistar大鼠16种不同组织的9种Na^＋通道α亚单位及1种β亚单位的mRNA进行检测发现：同种类型Na^＋通道mRNA在大鼠不同组织中的表达不同,不同类型Na^＋通道mRNA在大鼠同一组织中的表达不同.其中,神经系统和心肌组织中Na^＋通道mRNA的表达最高,随着日龄的增加,Na^＋通道mRNA在不同组织中表达的变化趋势不同.Na^＋通道在全身组织中的广泛分布及随发育周期的不同变化趋势,为离子通道病的研究及治疗提供了理论基础.

阿霉素致大鼠心肌损伤及抑制蛋白基因表达分析

目的 探索阿霉素致大鼠心肌损伤 H+- ATPaseβ-亚基及抑制蛋白基因表达的改变。方法 用 RT-PCR方法对心肌损伤 H+- ATPaseβ-亚基及抑制蛋白基因 m RNA水平表达进行定量分析。结果 与正常对照组相比 ,损伤组 H+- ATPaseβ-亚基 m RNA表达量明显下降 (P <0 .0 1) ;抑制蛋白 m RNA表达量改变不明显 (P>0 .0 5 )。结论 H+- ATPase催化亚基 m RNA水平表达量的降低 ,从基因表达水平影响心脏能量代谢 。

β-伴大豆球蛋白β亚基的纯化及免疫活性鉴定

等电点沉淀法和凝胶过滤层析提纯的β-伴大豆球蛋白经6mol·L-1脲变性后解聚为游离亚基,利用DEAE琼脂糖凝胶FF离子交换层析分离纯化β-伴大豆球蛋白亚基,并对纯化亚基进行透析复性。同时将β-伴大豆球蛋白免疫家兔制备抗血清,利用免疫印迹方法检测纯化的亚基与β-伴大豆球蛋白抗血清是否发生免疫反应。结果表明:利用DEAE琼脂糖凝胶FF阴离子交换层析可以纯化出高纯度的β-伴大豆球蛋白β亚基,纯化的β亚基可以与抗β-伴大豆球蛋白抗体结合,具有免疫活性。

中国大鲵脑cDNA文库构建及促甲状腺激素β亚基基因cDNA的克隆和序列分析

以大鲵脑组织为材料,提取总RNA,应用CloneminerTM文库构建技术构建了cDNA文库。经检测,文库初始滴度为5.0×105cfu.mL-1,重组率为91.70%,插入片断大小在0.35～3.9kb,平均插入片段大小为0.791kb,文库扩增后滴度为4.0×109cfu.mL-1。随机挑选200个阳性克隆测序,经生物信息学分析,发现20个片段与已报道的基因有较高同源性,包括促甲状腺激素基因、生长激素基因及催乳素基因等,其中三个克隆为促甲状腺激素β亚基(TSHβ)基因。序列分析表明,TSHβcDNA全长序列为705bp,包含417bp开放读码框,编码138个氨基酸序列,其中前19个氨基酸为大鲵TSHβ亚基信号肽部分,后接119个氨基酸组成的TSHβ亚基成熟肽。同源性分析显示,大鲵TSHβ亚基与两栖类牛蛙、蟾蜍及爪蟾同一蛋白的同源性分别为53.6%、52.2%和60.3%。采用邻接法和最大简约法对部分脊椎动物TSHβ氨基酸序列构建分子系统树,结果显示有尾目大鲵为两栖动物中较早分化的一支,表明其进化地位较原始。RT-PCR组织分布分析发现,TSHβ基因除垂体有表达外,性腺也有少量表达。

人绒毛膜促性腺激素游离β亚单位磁分离酶联免疫方法的建立

目的建立一种新的测定人绒毛膜促性腺激素游离β亚单位(hCGβ)磁分离酶联免疫分析法(MEIA)。方法用识别不同表位的两株单克隆抗体(mAb),一株mAb用FITC标记,另一株用碱性磷酸酶(AP)标记;以偶联羊抗FITC抗体的磁珠作为固相,以酚酞单磷酸酯溶液为底物,建立测定hCGβ磁分离酶免疫测定法。结果本MEIA法的灵敏度为0.1IU/L,批内CV小于8.5%,批间CV小于14%,平均稀释回收率为92.5%;与促黄体生成激素(leuteinizinghormone,LH)、促甲状腺激素(thyroidstimulatinghormone,TSH)和促卵泡成熟激素(folliclestimulatinghormone,FSH)均无交叉反应,与完整的hCG(1000IU/L)的交叉反应为1.2%,有效期不低于14个月。结论本方法的性能优于现有的放射免疫(RIA)和ELISA试剂盒,接近进口同类试剂的水平,有助于为市场提供一种高质量而价廉的hCGβ测定试剂盒。