LIM-Nebulette reinforces podocyte structural integrity by linking actin and vimentin filaments

Xuhua Ge, Tao Zhang, Xiaoxia Yu, Alecia N. Muwonge, Nanditha Anandakrishnan, Nicholas J. Wong, Jonathan C. Haydak, Jordan M. Reid, Jia Fu, Jenny S. Wong, Smiti Bhattacharya, Christina M. Cuttitta, Fang Zhong, Ronald E. Gordon, Fadi Salem, William Janssen, James C. Hone, Aihua Zhang, Hong Li, John C. HeG. Luca Gusella, Kirk N. Campbell, Evren U. Azeloglu

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

Background Maintenance of the intricate interdigitating morphology of podocytes is crucial for glomerular filtration. One of the key aspects of specialized podocyte morphology is the segregation and organization of distinct cytoskeletal filaments into different subcellular components, for which the exact mechanisms remain poorly understood. Methods Cells from rats, mice, and humans were used to describe the cytoskeletal configuration underlying podocyte structure. Screening the time-dependent proteomic changes in the rat puromycin aminonucleoside-induced nephropathy model correlated the actin-binding protein LIM-nebulette strongly with glomerular function. Single-cell RNA sequencing and immunogold labeling were used to determine Nebl expression specificity in podocytes. Automated high-content imaging, super-resolution microscopy, atomic force microscopy (AFM), live-cell imaging of calcium, and measurement of motility and adhesion dynamics characterized the physiologic role of LIM-nebulette in podocytes. Results Nebl knockout mice have increased susceptibility to adriamycin-induced nephropathy and display morphologic, cytoskeletal, and focal adhesion abnormalities with altered calcium dynamics, motility, and Rho GTPase activity. LIM-nebulette expression is decreased in diabetic nephropathy and FSGS patients at both the transcript and protein level. In mice, rats, and humans, LIM-nebulette expression is localized to primary, secondary, and tertiary processes of podocytes, where it colocalizes with focal adhesions as well as with vimentin fibers. LIM-nebulette shRNA knockdown in immortalized human podocytes leads to dysregulation of vimentin filament organization and reduced cellular elasticity as measured by AFM indentation. Conclusions LIM-nebulette is a multifunctional cytoskeletal protein that is critical in the maintenance of podocyte structural integrity through active reorganization of focal adhesions, the actin cytoskeleton, and intermediate filaments.

Original languageEnglish (US)
Pages (from-to)2372-2391
Number of pages20
JournalJournal of the American Society of Nephrology
Volume31
Issue number10
DOIs
StatePublished - Oct 2020

All Science Journal Classification (ASJC) codes

  • Nephrology

Fingerprint

Dive into the research topics of 'LIM-Nebulette reinforces podocyte structural integrity by linking actin and vimentin filaments'. Together they form a unique fingerprint.

Cite this