Yom Din S, Hurvitz A, Goldberg D, Jackson K, Levavi-Sivan B, Degani G
Department of Animal Sciences, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot, Israel.
J Endocrinol Invest. 2008 Mar;31(3):201-10. doi: 10.1007/BF03345591.
In this study, the GH and IGF-I of the Russian sturgeon (rs), Acipenser gueldenstaedtii, were cloned and sequenced, and their mRNA gene expression determined. In addition, to improve our understanding of the GH function, the expression of this hormone was assessed in young males and females. Moreover, IGF-I expression was quantified in young males and compared to that in older ones. The nucleotide sequence of the rsGH cDNA was 980 bp long and had an open reading frame of 642 bp, beginning with the first ATG codon at position 39 and ending with the stop codon at position 683. A putative polyadenylation signal, AATAAA, was recognized 42 bp upstream of the poly (A) tail. The position of the signal- peptide cleavage site was predicted to be at position 111, yielding a signal peptide of 24 amino-acids (aa) and a mature peptide of 190 aa. When the rsGH aa sequence was compared with other species, the highest degree of identity was found to be with mammalians (66-70% identity), followed by anguilliformes and amphibia (61%) and other fish (39-47%). The level of rsGH mRNA was discovered to be similar in pituitaries of females and males of 5 age groups (1, 2, 3, 4, and 5- yr-old). In females and males, the levels did not change dramatically during the first 5 yr of growth. The partial nucleotide sequence of the rsIGF-I was 445 bp long and had an open reading frame of 396 bp, beginning with the ATG codon at position 50. The position of the signal-peptide cleavage site was predicted to be at position 187, yielding a signal peptide of 44 aa. The highest level of IGF-I mRNA expression was recorded in the kidney of adult sturgeons. The IGF-I mRNA expression levels in the intestine, pituitary gland, and liver were not significantly different. Low levels of expression were found in the brain, heart, and muscle. In most tissues, there was no significant difference between mRNA levels of one and 5-yr-old fish. In conclusion, based on the GH-sequence analysis, A. gueldenstaedtii is genetically distant from other teleosts. The expression of the GH mRNA was similar in males and females, and its level remained constant during the first 5 yr of growth. While the IGF-I mRNA expression differed amongst various tissues, the level in each tissue was similar in 1 and 5-yr-old fish.
在本研究中，对俄罗斯鲟（Acipenser gueldenstaedtii，rs）的生长激素（GH）和胰岛素样生长因子-I（IGF-I）进行了克隆和测序，并测定了它们的mRNA基因表达。此外，为了增进我们对GH功能的理解，评估了该激素在年轻雄性和雌性中的表达。此外，对年轻雄性的IGF-I表达进行了定量，并与年长雄性的表达进行了比较。rsGH cDNA的核苷酸序列长980 bp，有一个642 bp的开放阅读框，从第39位的第一个ATG密码子开始，到第683位的终止密码子结束。在poly（A）尾上游42 bp处识别出一个假定的聚腺苷酸化信号AATAAA。信号肽切割位点的位置预计在第111位，产生一个24个氨基酸（aa）的信号肽和一个190 aa的成熟肽。当将rsGH的氨基酸序列与其他物种进行比较时，发现与哺乳动物的同一性程度最高（同一性为66 - 70%），其次是鳗鲡目和两栖类（61%）以及其他鱼类（39 - 47%）。发现5个年龄组（1、2、3、4和5岁）的雌性和雄性垂体中rsGH mRNA水平相似。在雌性和雄性中，生长的前5年期间该水平没有显著变化。rsIGF-I的部分核苷酸序列长445 bp，有一个396 bp的开放阅读框，从第50位的ATG密码子开始。信号肽切割位点的位置预计在第187位，产生一个44 aa的信号肽。在成年鲟鱼的肾脏中记录到IGF-I mRNA的最高表达水平。在肠道、垂体和肝脏中IGF-I mRNA的表达水平没有显著差异。在脑、心脏和肌肉中发现表达水平较低。在大多数组织中，1岁和5岁鱼的mRNA水平没有显著差异。总之，基于GH序列分析，俄罗斯鲟在遗传上与其他硬骨鱼相距较远。GH mRNA在雄性和雌性中的表达相似，并且在生长的前5年期间其水平保持恒定。虽然IGF-I mRNA在不同组织中的表达有所不同，但在1岁和5岁鱼的每个组织中该水平相似。
