The intermediate filament protein nestin serves as a molecular hub for smooth muscle cytoskeletal signaling

Abstract

Background The recruitment of the actin-regulatory proteins cortactin and profilin-1 (Pfn-1) to the membrane is important for the regulation of actin cytoskeletal reorganization and smooth muscle contraction. Polo-like kinase 1 (Plk1) and the type III intermediate filament protein vimentin are involved in smooth muscle contraction. Regulation of complex cytoskeletal signaling is not entirely elucidated. The aim of this study was to evaluate the role of nestin (a type VI intermediate filament protein) in cytoskeletal signaling in airway smooth muscle. Methods Nestin expression in human airway smooth muscle (HASM) was knocked down by specific shRNA or siRNA. The effects of nestin knockdown (KD) on the recruitment of cortactin and Pfn-1, actin polymerization, myosin light chain (MLC) phosphorylation, and contraction were evaluated by cellular and physiological approaches. Moreover, we assessed the effects of non-phosphorylatable nestin mutant on these biological processes. Results Nestin KD reduced the recruitment of cortactin and Pfn-1, actin polymerization, and HASM contraction without affecting MLC phosphorylation. Moreover, contractile stimulation enhanced nestin phosphorylation at Thr-315 and the interaction of nestin with Plk1. Nestin KD also diminished phosphorylation of Plk1 and vimentin. The expression of T315A nestin mutant (alanine substitution at Thr-315) reduced the recruitment of cortactin and Pfn-1, actin polymerization, and HASM contraction without affecting MLC phosphorylation. Furthermore, Plk1 KD diminished nestin phosphorylation at this residue. Conclusions Nestin is an essential macromolecule that regulates actin cytoskeletal signaling via Plk1 in smooth muscle. Plk1 and nestin form an activation loop during contractile stimulation.

Molecular mechanism of bitter taste receptor agonist‐mediated relaxation of airway smooth muscle

“…HIPPO signaling modulates actin cytoskeleton restructuring via changes in components such as 14-3-3 and Yes-associated protein (YAP) 51,52 ; regulation of the actin cytoskeleton plays a significant role in regulating both ASM cell contraction and proliferation. [53][54][55] Rho GTPases are necessary for the nuclear localization of YAP1, where it functions as a co-activator of transcription factors driving the expression of genes important for proliferation and contraction. Gene silencing of ARHGEF12 in MCF7 breast cancer cells resulted in lower levels of YAP1 activation (increased S127 phosphorylation) and phalloidin-stained F-actin.…”

“…In addition to identifying agonist‐specific regulation of RhoA‐related signaling, our phosphoproteomic data also identified GPCR‐specific regulation of the HIPPO signaling pathway. HIPPO signaling modulates actin cytoskeleton restructuring via changes in components such as 14–3‐3 and Yes‐associated protein (YAP) 51,52 ; regulation of the actin cytoskeleton plays a significant role in regulating both ASM cell contraction and proliferation 53–55 . Rho GTPases are necessary for the nuclear localization of YAP1, where it functions as a co‐activator of transcription factors driving the expression of genes important for proliferation and contraction.…”

A One-Step Plasma Assisted Synthesis of Gold Nanoparticles and Simultaneous Linker-Free Conjugation with Nestin: An In Vitro Study of Cellular toxicity

“…Notably, GNPs exhibit a high loading capacity with multiple ligands (chemical and biomolecules) [21]. In this study we used NES, a type VI intermediate filament protein [22] as a ligand which is mostly expressed in neural stem and progenitor cells during embryonic development and neurogenesis [23] Its versatile expression is notably evident in various tissues, including neural tissue [24], where it plays a pivotal role in the structural organization of neural precursor cells, contributing significantly to the development of the nervous system [25]. Beyond neural tissue, NES makes its presence known in blood vessels [26], specifically in the endothelial cells during embryonic development and under certain pathological conditions such as tumor angiogenesis [27] —signifying its involvement in the formation of blood vessels within tumors.…”