AZTI-Tecnalia, Marine Research Division, Txatxarramendi Ugartea z/g, 48395 Sukarrieta, Bizkaia, Spain.
Department of Zoology and Animal Cell Biology, Research Centre for Experimental Marine Biology and Biotechnology (PIE-UPV/EHU), University of the Basque Country, Areatza z/g, Plentzia, Bizkaia, Spain.
Gene. 2014 May 10;541(1):8-18. doi: 10.1016/j.gene.2014.03.006. Epub 2014 Mar 7.
Telomerase is a reverse transcriptase ribonucleoprotein that maintains the ends of linear chromosomes. This enzyme plays a major role in cell processes like proliferation, differentiation and tumorigenesis, being associated with aging and survival of species. In this study, the gene coding for TERT (Telomerase Reverse Transcriptase) of two commercial fish species, European hake (Merluccius merluccius) and Atlantic cod (Gadus morhua), has been partially cloned. A fragment of 1581bp (hake) and 633bp (cod) showed high homology (identity 74%, query cover 99%, E-value=0) with known Perciformes TERT sequences. TERT transcription patterns were assessed by qRT-PCR in different tissues of hake (brain, ovary, testis, muscle, skin, gills, liver and kidney) and cod (brain, muscle and skin) of different sizes/ages in order to understand its role in the physiological aging of teleosts. TERT was found to be ubiquitously transcribed in all tissues and size/age groups studied in both species. Significantly higher relative transcription levels (p<0.05) were found with increasing size/age of M. merluccius in the kidney, muscle, skin and gonad, the latter exhibiting particularly high relative transcription levels. Male hakes showed higher TERT relative transcription levels in the brain, gonad and liver than females, although these differences were not statistically significant (p<0.05). In G. morhua, higher TERT relative transcription levels were recorded in the muscle and brain of fry and juvenile individuals. Therefore, TERT relative transcription pattern exhibited a higher telomerase demand in early developmental stages and also in mature stages, suggesting tissue renewal or regeneration processes as a conserved mechanism for maintaining long-term cell proliferation capacity and preventing senescence. Thus, it can be concluded that TERT relative transcription level was species and tissue specific and changed with the age of fishes.
端粒酶是一种逆转录酶核糖核蛋白，可维持线性染色体的末端。这种酶在细胞增殖、分化和肿瘤发生等过程中起着重要作用，与物种的衰老和存活有关。在这项研究中，部分克隆了两种商业鱼类，欧鳎（Merluccius merluccius）和大西洋鳕鱼（Gadus morhua）的 TERT（端粒酶逆转录酶）基因。一段 1581bp（鳎）和 633bp（鳕鱼）的片段与已知的鲈形目 TERT 序列具有高度同源性（同一性 74%，查询覆盖率 99%，E 值=0）。通过 qRT-PCR 在不同大小/年龄的鳎（脑、卵巢、睾丸、肌肉、皮肤、鳃、肝和肾）和鳕鱼（脑、肌肉和皮肤）的不同组织中评估了 TERT 的转录模式，以了解其在硬骨鱼生理衰老中的作用。结果表明，在这两个物种的所有组织和研究的大小/年龄组中，TERT 都普遍转录。在 M. merluccius 的肾脏、肌肉、皮肤和性腺中，随着大小/年龄的增加，相对转录水平显著升高（p<0.05），后者表现出特别高的相对转录水平。与雌性相比，雄性鳎在脑、性腺和肝脏中的 TERT 相对转录水平更高，但这些差异没有统计学意义（p<0.05）。在 G. morhua 中，幼鱼和幼鱼个体的肌肉和大脑中记录到更高的 TERT 相对转录水平。因此，TERT 相对转录模式在早期发育阶段和成熟阶段都表现出更高的端粒酶需求，这表明组织更新或再生过程是维持长期细胞增殖能力和防止衰老的保守机制。因此，可以得出结论，TERT 相对转录水平具有物种和组织特异性，并随鱼类年龄的变化而变化。
