Ali Muhammad Y, Pavasovic Ana, Dammannagoda Lalith K, Mather Peter B, Prentis Peter J
School of Earth, Environmental and Biological Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
School of Biomedical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
PeerJ. 2017 Aug 24;5:e3623. doi: 10.7717/peerj.3623. eCollection 2017.
Systemic acid-base balance and osmotic/ionic regulation in decapod crustaceans are in part maintained by a set of transport-related enzymes such as carbonic anhydrase (CA), Na/K-ATPase (NKA), H-ATPase (HAT), Na/K/2Cl cotransporter (NKCC), Na/Cl/HCO[Formula: see text] cotransporter (NBC), Na/H exchanger (NHE), Arginine kinase (AK), Sarcoplasmic Ca-ATPase (SERCA) and Calreticulin (CRT). We carried out a comparative molecular analysis of these genes in three commercially important yet eco-physiologically distinct freshwater crayfish and , with the aim to identify mutations in these genes and determine if observed patterns of mutations were consistent with the action of natural selection. We also conducted a tissue-specific expression analysis of these genes across seven different organs, including gills, hepatopancreas, heart, kidney, liver, nerve and testes using NGS transcriptome data. The molecular analysis of the candidate genes revealed a high level of sequence conservation across the three Hyphy analysis revealed that all candidate genes showed patterns of molecular variation consistent with neutral evolution. The tissue-specific expression analysis showed that 46% of candidate genes were expressed in all tissue types examined, while approximately 10% of candidate genes were only expressed in a single tissue type. The largest number of genes was observed in nerve (84%) and gills (78%) and the lowest in testes (66%). The tissue-specific expression analysis also revealed that most of the master genes regulating pH and osmoregulation (CA, NKA, HAT, NKCC, NBC, NHE) were expressed in all tissue types indicating an important physiological role for these genes outside of osmoregulation in other tissue types. The high level of sequence conservation observed in the candidate genes may be explained by the important role of these genes as well as potentially having a number of other basic physiological functions in different tissue types.
十足目甲壳动物的全身酸碱平衡以及渗透压/离子调节部分由一组与转运相关的酶维持，如碳酸酐酶（CA）、钠钾ATP酶（NKA）、氢ATP酶（HAT）、钠钾氯协同转运蛋白（NKCC）、钠氯碳酸氢根协同转运蛋白（NBC）、钠氢交换体（NHE）、精氨酸激酶（AK）、肌浆网钙ATP酶（SERCA）和钙网蛋白（CRT）。我们对三种具有商业重要性但生态生理学上不同的淡水小龙虾中的这些基因进行了比较分子分析，目的是识别这些基因中的突变，并确定观察到的突变模式是否与自然选择的作用一致。我们还利用NGS转录组数据对这些基因在鳃、肝胰腺、心脏、肾脏、肝脏、神经和睾丸等七个不同器官中的组织特异性表达进行了分析。对候选基因的分子分析显示，这三种（原文未明确三种是什么，根据前文推测是三种淡水小龙虾）之间具有高度的序列保守性。Hyphy分析表明，所有候选基因都显示出与中性进化一致的分子变异模式。组织特异性表达分析表明，46%的候选基因在所有检测的组织类型中都有表达，而约10%的候选基因仅在单一组织类型中表达。在神经（84%）和鳃（78%）中观察到的基因数量最多，在睾丸中最少（66%）。组织特异性表达分析还表明，大多数调节pH值和渗透压调节的主要基因（CA、NKA、HAT、NKCC、NBC、NHE）在所有组织类型中都有表达，这表明这些基因在渗透压调节之外的其他组织类型中具有重要的生理作用。在候选基因中观察到的高度序列保守性可能是由于这些基因的重要作用以及在不同组织类型中可能具有许多其他基本生理功能。
