AUTHOR=Luo Shengjie , Li Yongle , Li Shuwei , Jiang Renjun , Deng Fang , Liu Guoquan , Zhang Jianping 

TITLE=Expression Regulation of Water Reabsorption Genes and Transcription Factors in the Kidneys of Lepus yarkandensis

JOURNAL=Frontiers in Physiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.856427

DOI=10.3389/fphys.2022.856427

ISSN=1664-042X

ABSTRACT=<p><italic>Lepus yarkandensis</italic> is a desert-dwelling animal that has various adaptations to cope with drought. The kidney maintains water and acid-base balance mainly through the vasopressin-regulated water reabsorption pathway and proximal tubular bicarbonate reabsorption pathway. In this study, we compared the differentially expressed genes (DEGs) and transcription factors in the kidneys of <italic>L. yarkandensis</italic> and <italic>Oryctolagus cuniculus</italic> to explore the relationship between the DEGs in kidneys and the animals’ adaptations. Transcriptome sequencing data were used to predict the differentially-expressed water reabsorption genes and their transcription factors. Quantitative real-time PCR, immunohistochemistry, and western blotting were used to detect and verify the expression of DEGs in the kidney at mRNA and protein levels. Transcriptome analysis of the kidney of <italic>L. yarkandensis</italic> and <italic>O. cuniculus</italic> showed that 6,610 genes were up-regulated and 5,727 genes down-regulated in data shared by both species. According to the data, 232 transcription factors and their corresponding target genes were predicted, from which genes and transcription factors related to renal water reabsorption were screened. Quantitative RT-PCR results showed <italic>AQP1</italic>, <italic>AQP2</italic>, <italic>ADCY3</italic>, <italic>HIF1A</italic>, <italic>CREB3</italic>, and <italic>NFATc1</italic> had higher expression in the <italic>L. yarkandensis</italic> kidney; in comparison, <italic>FXYD2</italic> mRNA expression levels were lower. In western blotting, transcription factors <italic>HIF1A</italic>, <italic>NFATc1</italic>, <italic>NF-κB1</italic>, and critical genes <italic>ADCY3</italic>, <italic>ATPA1</italic>, and <italic>SLC4A4</italic>, were highly expressed in the kidneys of <italic>L. yarkandensis</italic>. Immunohistochemical results showed that the <italic>ADCY3</italic> protein was in the basolateral membrane of the collecting duct, the <italic>ATP1A1</italic> protein was in the basolateral membrane and medulla of proximal tubules, and the <italic>SLC4A4</italic> protein was in the basolateral membrane of proximal tubules. According to these results can be inferred that <italic>HIF1A</italic>, <italic>NFATc1</italic>, and <italic>NF-κB1</italic> play a certain role in regulating the expression of genes related to water reabsorption in the kidney of <italic>L. yarkandensis</italic>, thus improving the water reclamation efficiency of <italic>L. yarkandensis</italic>, so as to adapt to the arid desert environment.</p>