GATA2 regulates body water homeostasis through maintaining aquaporin 2 expression in renal collecting ducts.
GATA2 regulates body water homeostasis through maintaining aquaporin 2 expression in renal collecting ducts.
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GATA2 通过维持肾集合管中水通道蛋白 2 的表达来调节体内水分稳态。
DOI：
10.1128/mcb.01659-13
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发表时间：
2014
影响因子：
5.3
通讯作者：
Yamamoto,Masayuki
中科院分区：
文献类型：
--
作者：
Yu,Lei;Moriguchi,Takashi;Souma,Tomokazu;Takai,Jun;Satoh,Hironori;Morito,Naoki;Engel,JamesDouglas;Yamamoto,Masayuki
转录因子GATA 2在早期肾脏发育中起着关键作用，但其在成年肾脏中的分布和生理功能尚不清楚。我们通过在Gata 2 GFP/+小鼠中追踪绿色荧光蛋白（GFP）荧光来检查GATA 2在成年肾脏中的表达模式，所述Gata 2 GFP/+小鼠重现内源性GATA 2表达，并且发现特异性地在肾髓质中的稳健GFP表达。在纯化GFP阳性细胞后，我们发现集合管（CD）特异性标记物，包括水通道蛋白2（Aqp 2），一种重要的尿液水重吸收通道，大量表达。为了阐明GATA 2在CD细胞中的生理功能，我们通过将Gata 2 floxed小鼠与可诱导的Pax 8-Cremice杂交来产生肾小管细胞特异性Gata 2缺陷小鼠（Gata 2-CKO）。我们发现Gata 2-CKO小鼠的Aqp 2表达显著降低。Gata 2-CKO小鼠表现出高24小时尿量和低尿渗透压，这是尿崩症的两个重要体征。我们将生物素标记的GATA 2导入小鼠CD衍生细胞系并进行染色质下拉试验，结果显示GATA 2与Aqp 2启动子区域的保守加塔基序直接结合。利用Aqp 2启动子-报告基因的荧光素酶报告基因分析表明，GATA 2通过加塔基序反式激活Aqp 2。这些结果表明GATA 2调节CD细胞中Aqp 2基因的表达，并有助于维持体内水分稳态。
The transcription factor GATA2 plays pivotal roles in early renal development, but its distribution and physiological functions in adult kidney are largely unknown. We examined the GATA2 expression pattern in the adult kidney by tracing green fluorescent protein (GFP) fluorescence inGata2GFP/+mice that recapitulate endogenous GATA2 expression and found a robust GFP expression specifically in the renal medulla. Upon purification of the GFP-positive cells, we found that collecting duct (CD)-specific markers, including aquaporin 2 (Aqp2), an important channel for water reabsorption from urine, were abundantly expressed. To address the physiological function of GATA2 in the CD cells, we generated renal tubular cell-specificGata2-deficient mice (Gata2-CKO) by crossingGata2floxed mice with induciblePax8-Cremice. We found that theGata2-CKO mice showed a significant decrease inAqp2expression. TheGata2-CKO mice exhibited high 24-h urine volume and low urine osmolality, two important signs of diabetes insipidus. We introduced biotin-tagged GATA2 into a mouse CD-derived cell line and conducted chromatin pulldown assays, which revealed direct GATA2 binding to conserved GATA motifs in theAqp2promoter region. A luciferase reporter assay using anAqp2promoter-reporter showed that GATA2transactivatesAqp2through the GATA motifs. These results demonstrate that GATA2 regulates theAqp2gene expression in CD cells and contributes to the maintenance of the body water homeostasis.