MOLECULAR-CLONING AND EXPRESSION OF THE CHICKEN SMOOTH-MUSCLE GAMMA-ACTIN MESSENGER-RNA
MOLECULAR-CLONING AND EXPRESSION OF THE CHICKEN SMOOTH-MUSCLE GAMMA-ACTIN MESSENGER-RNA
复制标题
DOI：
10.1002/cm.970240108
复制
发表时间：
1993-01-01
影响因子：
--
通讯作者：
ZIMMER, WE
中科院分区：
文献类型：
--
作者：
KOVACS, AM;ZIMMER, WE
我们通过分离和鉴定代表这种肌动蛋白异构体的cDNA，并利用cDNA探测来自成年和发育细胞的RNA，研究了鸡平滑肌γ -肌动蛋白mRNA的表达。对全长平滑肌γ -肌动蛋白cDNA进行核苷酸序列分析，结果表明该cDNA含有94 bp的5′非翻译序列、1131 bp的开放阅读框和97 bp的3′非翻译序列。从鸡cDNA中推断出的376个氨基酸序列中，在NH2-和cooh -末端区域有诊断性氨基酸，这明确地鉴定了肠平滑肌肌动蛋白亚型。此外，从我们的cDNA克隆中推断出的鸡γ -肠肌动蛋白与早期蛋白质研究中报道的序列不同[J]。Vandekerckhove和K. Weber, FEBS Lett. 102:219, 1979]通过在蛋白质的359位含有脯氨酸而不是谷氨酰胺，表明鸟类-肠肌动蛋白同型物与哺乳动物相同。将鸡cDNA的5′和3′非翻译序列与大鼠、小鼠和人的序列进行比较，发现这些mrna在编码区外不存在高度的跨物种序列保守性。Northern杂交分析表明，γ -肠肌动蛋白mRNA在成人主动脉和输卵管组织中表达，而在成人骨骼肌、心肌、肝脏、脑和脾脏组织中不表达。在胚胎4-5天的砂囊组织中首次观察到可测量的γ -肠肌动蛋白mRNA，并在胚胎16-17天的平滑肌细胞中含量增加。在胚胎发育过程中，γ -肠肌动蛋白mRNA的含量在最初的增加之后出现下降，直到大约7天后，在成年砂囊组织中含量增加到最高水平。总的来说，在以前的研究中观察到的肠内γ -肌动蛋白的发育外观与此蛋白相似，表明在肌肉形成过程中，平滑肌γ -肌动蛋白的发育表达在一定程度上受到鸡内脏平滑肌细胞mRNA含量增加的调节。
We have investigated the expression of chicken smooth muscle gamma-actin mRNA by isolation and characterization of cDNAs representing this actin isoform and utilizing the cDNA to probe RNA from adult and developing cells. Nucleotide sequence elucidated from an apparent full length smooth muscle gamma-actin cDNA revealed that it contained 94 bp of 5' non-translated sequence, an open reading frame of 1131 bp, and 97 bp of 3' non-translated sequence. Within the 376 amino acid sequence deduced from the chicken cDNA were diagnostic amino acids at the NH2- and COOH-terminal regions which provided unequivocal identification of the gamma-enteric smooth muscle actin isoform. In addition, the chicken gamma-enteric actin deduced from our cDNA clones was found to differ from the sequence reported in earlier protein studies [J. Vandekerckhove and K. Weber, FEBS Lett. 102:219, 1979] by containing a proline rather than a glutamine at position 359 of the protein, indicating that the avian gamma-enteric actin isoform is identical to its mammalian counterpart. Comparison of the 5' and 3' non-translated sequence determined from the chicken cDNA to that elucidated for rat, mouse, and human showed that there is not a high degree of cross-species sequence conservation outside of the coding regions among these mRNAs. Northern hybridization analyses demonstrated that the gamma-enteric actin mRNA is expressed in adult aorta and oviduct tissues but not in adult skeletal muscle, cardiac muscle, liver, brain, and spleen tissues. The gamma-enteric actin mRNA was first observed in measurable quantities in gizzard tissue from 4-5 day embryos and increased in content in developing smooth muscle cells through 16-17 embryonic days. Following this initial increase during embryonic development, the gamma-enteric actin mRNA exhibits a decline in content until approximately 7 days posthatching, after which there is an increase in content to maximal levels found in adult gizzard tissue. In general, the developmental appearance of the gamma-enteric mRNA parallels that observed for this protein in previous studies indicating that the developmental expression of smooth muscle gamma-actin is regulated, in part, by an increased content of mRNA in chicken visceral smooth muscle cells during myogenesis.