Felix-Portillo Monserrath, Martinez-Quintana José A, Peregrino-Uriarte Alma B, Yepiz-Plascencia Gloria
Centro de Investigación en Alimentación y Desarrollo. A.C., P.O. Box 1735. Carretera a Ejido La Victoria Km. 0.6 Hermosillo, Sonora 83304, Mexico.
Centro de Investigación en Alimentación y Desarrollo. A.C., P.O. Box 1735. Carretera a Ejido La Victoria Km. 0.6 Hermosillo, Sonora 83304, Mexico.
Mar Environ Res. 2014 Oct;101:91-100. doi: 10.1016/j.marenvres.2014.09.005. Epub 2014 Sep 26.
Aquatic animals encounter variation in oxygen tension that leads to the accumulation of reactive oxygen species (ROS) that can harm the organisms. Under these circumstances some organisms have evolved to tolerate hypoxia. In mammals, metallothioneins (MTs) protect against hypoxia-generated ROS. Here we report the MT gene from the shrimp Litopenaeus vannamei (LvMT). LvMT is differentially expressed in hemocytes, intestine, gills, pleopods, heart, hepatopancreas and muscle, with the highest levels in hepatopancreas and heart. LvMT mRNA increases during hypoxia in hepatopancreas and gills after 3 h at 1.5 mg L(-1) dissolved oxygen (DO). This gene structure resembles the homologs from invertebrates and vertebrates possessing three exons, two introns and response elements for metal response transcription factor 1 (MTF-1), hypoxia-inducible factor 1 (HIF-1) and p53 in the promoter region. During hypoxia, HIF-1/MTF-1 might participate inducing MT to contribute towards the tolerance to ROS toxicity. MT importance in aquatic organisms may include also ROS-detoxifying processes.
水生动物会遇到氧张力的变化，这会导致活性氧（ROS）的积累，而ROS会对生物体造成伤害。在这种情况下，一些生物已经进化出耐受缺氧的能力。在哺乳动物中，金属硫蛋白（MTs）可抵御缺氧产生的ROS。在此，我们报道了凡纳滨对虾（Litopenaeus vannamei）的MT基因（LvMT）。LvMT在血细胞、肠道、鳃、腹足、心脏、肝胰腺和肌肉中差异表达，在肝胰腺和心脏中的表达水平最高。在溶解氧（DO）为1.5 mg L⁻¹的条件下缺氧3小时后，肝胰腺和鳃中的LvMT mRNA增加。该基因结构类似于来自无脊椎动物和脊椎动物的同源物，具有三个外显子、两个内含子，并且在启动子区域具有金属反应转录因子1（MTF-1）、缺氧诱导因子1（HIF-1）和p53的反应元件。在缺氧期间，HIF-1/MTF-1可能参与诱导MT，以促进对ROS毒性的耐受性。MT在水生生物中的重要性可能还包括ROS解毒过程。
