脊椎動(dòng)物腎小球中的濾血障礙層（血液在此被超濾形成尿）由被稱為“足細(xì)胞”的發(fā)生改變的上皮細(xì)胞構(gòu)成。腎單元（由腎小球和腎小管組成）被認(rèn)為是脊椎動(dòng)物的一個(gè)典型的適應(yīng)性特征,。但“類(lèi)似腎單元”的特征也見(jiàn)于很多無(wú)脊椎動(dòng)物的排泄系統(tǒng),。
現(xiàn)在Weavers等人報(bào)告,，昆蟲(chóng)的一種被稱為“腎原細(xì)胞”的過(guò)濾細(xì)胞與“足細(xì)胞”有驚人的相似之處。腎臟裂孔隔膜主要成分的果蠅直系同源物形成一種由相互作用的蛋白構(gòu)成的復(fù)合物,，與脊椎動(dòng)物中的相似,。“腎原細(xì)胞”隔膜在腎病蛋白或neph1直系同源基因的果蠅突變體中完全丟失,，與人類(lèi)腎病—— “先天性腎病綜合征”(NPHS1)的表現(xiàn)型相似,。這一發(fā)現(xiàn)將昆蟲(chóng)“腎原細(xì)胞”確定為研究腎臟“足細(xì)胞”生物學(xué)及與“足細(xì)胞”相關(guān)疾病的一個(gè)模型。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature 457, 322-326 (15 January 2009) | doi:10.1038/nature07526
The insect nephrocyte is a podocyte-like cell with a filtration slit diaphragm
Helen Weavers1,6, Silvia Prieto-Sánchez2,6, Ferdinand Grawe3, Amparo Garcia-López4, Ruben Artero4, Michaela Wilsch-Br?uninger5, Mar Ruiz-Gómez2, Helen Skaer1 & Barry Denholm1
1 Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
2 Centro de Biología Molecular Severo Ochoa, CSIC, UAM, Cantoblanco, 28049 Madrid, Spain
3 Institut für Genetik, Heinrich-Heine-Universit?t, Düsseldorf D-40225, Germany
4 Department of Genetics, University of Valencia, Burjasot, Valencia 46100, Spain
5 Max Planck Institute of Molecular Cell Biology and Genetics, Dresden D-01307, Germany
The nephron is the basic structural and functional unit of the vertebrate kidney. It is composed of a glomerulus, the site of ultrafiltration, and a renal tubule, along which the filtrate is modified. Although widely regarded as a vertebrate adaptation1, 'nephron-like' features can be found in the excretory systems of many invertebrates, raising the possibility that components of the vertebrate excretory system were inherited from their invertebrate ancestors2. Here we show that the insect nephrocyte has remarkable anatomical, molecular and functional similarity to the glomerular podocyte, a cell in the vertebrate kidney that forms the main size-selective barrier as blood is ultrafiltered to make urine. In particular, both cell types possess a specialized filtration diaphragm, known as the slit diaphragm in podocytes or the nephrocyte diaphragm in nephrocytes. We find that fly (Drosophila melanogaster) orthologues of the major constituents of the slit diaphragm, including nephrin, NEPH1 (also known as KIRREL), CD2AP, ZO-1 (TJP1) and podocin, are expressed in the nephrocyte and form a complex of interacting proteins that closely mirrors the vertebrate slit diaphragm complex. Furthermore, we find that the nephrocyte diaphragm is completely lost in flies lacking the orthologues of nephrin or NEPH1—a phenotype resembling loss of the slit diaphragm in the absence of either nephrin (as in human congenital nephrotic syndrome of the Finnish type, NPHS1) or NEPH1. These changes markedly impair filtration function in the nephrocyte. The similarities we describe between invertebrate nephrocytes and vertebrate podocytes provide evidence suggesting that the two cell types are evolutionarily related, and establish the nephrocyte as a simple model in which to study podocyte biology and podocyte-associated diseases.
