14-3-3 λ protein interacts with ADF1 to regulate actin cytoskeleton dynamics in Arabidopsis

Abstract

Actin cytoskeleton dynamics is critical for variety of cellular events including cell elongation, division and morphogenesis, and is tightly regulated by numerous groups of actin binding proteins. However it is not well understood how these actin binding proteins are modulated in a physiological condition by their interaction proteins. In this study, we describe that Arabidopsis 14-3-3  protein interacted with actin depolymerizing factor 1 (ADF1) in plant to regulate F-actin stability and dynamics. Loss of 14-3-3  in Arabidopsis resulted in longer etiolated hypocotyls in dark and changed actin cytoskeleton architecture in hypocotyl cells. Overexpression of ADF1 repressed 14-3-3  mutant hypocotyl elongation and actin dynamic phenotype. In addition, the phosphorylation level of ADF1 was increased and the subcellular localization of ADF1 was altered in 14-3-3  mutant. Consistent with these observations, the actin filaments were more stable in 14-3-3  mutant. Our results indicate that 14-3-3  protein mediates F-actin dynamics possibly through inhibiting ADF1 phosphorylation in vivo.Arabidopsis, 14-3-3, ADF, phosphorylation, actin cytoskeleton dynamics Citation:Zhao SS, Zhao YX, Guo Y. 14-3-3  protein interacts with ADF1 to regulate actin cytoskeleton dynamics in

Clathrin light chains regulate hypocotyl elongation by affecting the polarization of the auxin transporter PIN3 in Arabidopsis

“…The clc2-1 clc3-1 mutant shows impaired microtubule arrangement and modified actin architecture in the hypocotyl Microtubules and the actin cytoskeleton play positive roles in regulating hypocotyl elongation by both shaping cells and providing directionality for elongation (Zhao et al, 2015). These observations prompted us to examine the roles of actin cytoskeletons and microtubules in hypocotyl elongation using clc2-1 clc3-1.…”

Plant actin depolymerizing factor: actin microfilament disassembly and more

“…Arabidopsis thaliana 14-3-3λ interacts with AtADF1 and regulates F-actin organization in vivo (Zhao et al 2015 ). However, contrary to what is expected from animal 14-3-3 that stabilizes phosphorylated ADF/cofilin thus suppresses F-actin depolymerizing activity of ADF/cofilin, a knockout mutant of 14-3-3λ exhibited an elongated hypocotyl phenotype, similarly to Atadf1 and Atadf4 .…”

“…However, contrary to what is expected from animal 14-3-3 that stabilizes phosphorylated ADF/cofilin thus suppresses F-actin depolymerizing activity of ADF/cofilin, a knockout mutant of 14-3-3λ exhibited an elongated hypocotyl phenotype, similarly to Atadf1 and Atadf4 . Authors also observed that a 14-3-3λ loss-of-mutant increased the phosphorylation level of AtADF1 thus hindered the proper localization of AtADF1 to F-actin (Zhao et al 2015 ). Therefore, the regulatory mechanism of ADF by 14-3-3 may differ between animals and plants.…”

NtWRKY-R1, a Novel Transcription Factor, Integrates IAA and JA Signal Pathway under Topping Damage Stress in Nicotiana tabacum

“…Yeast two-hybrid experiment further showed that NtWRKY-R1 could interact with the ABP/ADF (Figure 8 ). The ABP/ADF is considered as primary regulatory factor for the reorganization of the actin cytoskeleton (Maciver and Hussey, 2002 ; Zhao et al, 2015 ), which is involved in various cellular and developmental activities (Ketelaar et al, 2004 ; Kandasamy et al, 2007 ), as well as cell signaling in response to biotic and abiotic stresses (Hussey et al, 2002 ). The actin in the nucleus, as a structural protein, participates in the formation of the nuclear skeleton and chromatin skeleton, binds ADF to regulate chromatin structure and gene transcription, mRNA processing and transportation (Burgos-Rivera et al, 2008 ; Zheng et al, 2013 ; Fu et al, 2014 ; Henty-Ridilla et al, 2014 ).…”