Molecular Characterization and Expression of Vitellogenin Receptor from White Perch (Morone americana)1
Molecular Characterization and Expression of Vitellogenin Receptor from White Perch (Morone americana)1
复制标题
白鲈 (Morone americana)1 卵黄蛋白原受体的分子特征和表达
作者：
N. Hiramatsu;R. Chapman;J. Lindzey;Matthew Haynes;C. Sullivan
摘要从美洲鳗(Morone Americana)卵巢cDNA文库中克隆了脊椎动物卵黄蛋白原受体(VGR)的全长(4021个碱基对)基因，编码844个氨基酸，预测质量为93 kDa，具有其他结构特征。用地高辛标记的VGR cDNAs探针进行Northern印迹杂交，结果显示从发病前的鲈鱼卵巢中提取的∼有明显的4.1kb的杂交信号。推导的氨基酸序列与罗非鱼和虹鳟鱼的氨基酸序列同源性分别为%和82%。由于它有一个8个重复的配体结合域(LR8)，但缺少一个O-连接糖域(−)，因此它被鉴定为一个非O-连接形式的VGR(LR8−)。与所研究的其他脊椎动物，包括罗非鱼和鲑鱼不同，当使用假定的O-连接糖域两侧的引物集进行PCR筛选鲈鱼卵巢或肝脏mRNA逆转录本或cDNA文库时，没有检测到编码O-连接形式的VGR(LR8+)的mRNA的物种。这些新的发现质疑了这样的假设，即VGR的LR8+剪接变体总是主要存在于躯体组织中，并在卵巢组织中以较低的水平存在，以隔离与VG不同的脂蛋白。建立了一种基于SYBR-Green的实时逆转录聚合酶链式反应方法，并首次用于定量检测VGR在性腺和躯体组织中的表达，这在脊椎动物中尚属首次。Perch VGR mRNA表达的主要部位是卵巢，最大卵泡含有成石前卵母细胞的卵巢VGR mRNA表达水平最高。在卵黄发生过程中，VGR mRNA的表达随卵母细胞的生长而减少，在排卵卵中的表达非常有限。这些定量结果证实了这样一个概念，即发育中的卵母细胞必须广泛循环LR8−形式的VGR。
Abstract A full-length (4021 base pair [bp]) cDNA encoding a polypeptide (844 amino acids) with a predicted mass of 93 kDa and other characteristic structural features of a vertebrate vitellogenin receptor (VgR) was isolated from a white perch (Morone americana) ovarian cDNA library. Northern blotting performed using a specific digoxygenin-labeled VgR cDNA probe revealed a distinct ∼4.1 kilobase (kb) hybridization signal in an mRNA preparation obtained from previtellogenic perch ovaries. The deduced amino acid sequence of the perch VgR was 89% and 82% identical, respectively, to that of the tilapia and rainbow trout. Because it possessed an eight-repeat ligand-binding domain (LR8) but lacked an O-linked sugar domain (−), the perch VgR was identified as a non-O-linked form of VgR (LR8−). Unlike the case in other vertebrates investigated, including tilapia and trout, no species of mRNA encoding an O-linked form of VgR (LR8+) could be detected when perch ovarian or liver mRNA reverse transcripts or cDNA libraries were screened by PCR using primer sets flanking the putative O-linked sugar domain. These novel findings call into question the assumptions that an LR8+ splice variant of the VgR always is dominantly present in somatic tissues and exists at lower levels in ovarian tissues to sequester lipoproteins distinct from Vg. A SYBR-green-based real-time reverse transcription-polymerase chain reaction assay was developed and used to quantitatively measure VgR expression in gonadal and somatic tissues, for the first time in any vertebrate. The main site of perch VgR mRNA expression was the ovary and the highest level of VgR mRNA expression was in ovaries whose largest follicles contained previtellogenic oocytes. Expression of VgR mRNA decreased with oocyte growth during vitellogenesis and was very limited in ovulated eggs. These quantitative results verify the concept that growing oocytes must extensively recycle LR8− forms of the VgR.
甲状腺激素对大鼠骨骼肌中极低密度脂蛋白受体的调节。
DOI：
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发表时间：
1994
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Jokinen,EV;Landschulz,KT;Wyne,KL;Ho,YK;Frykman,PK;Hobbs,HH
通讯作者：
Hobbs,HH
DOI：
10.1016/s0021-9258(18)61318-3
发表时间：
1987-03
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
L. Opresko;H. Wiley
通讯作者：
L. Opresko;H. Wiley