Possible role of a septin, SEPT1, in spreading in squamous cell carcinoma DJM-1 cells

Abstract

We performed biochemical, histochemical and cell biological characterization of septins by focusing on SEPT1 in human skin tissues and a squamous cell carcinoma (SCC) cell line DJM-1. In immunoblotting, SEPT1, together with other septins, was detected in normal human epidermis, SCC and DJM-1. In immunohistochemical analyses, SEPT1 was detected diffusely in the cytoplasm of human epidermal cells and eccrine gland epithelial cells, and the protein level was increased in some skin tumors. In DJM-1 cells, SEPT1 together with other members of SEPT2-subgroup, SEPT4 and SEPT5, was enriched in lamellipodia and the localization was dependent on the cortical actin structure. SEPT1 distribution at lamellipodia was also observed in melanoma B16 cells. SEPT9, SEPT11 and SEPT14, in contrast, were localized along with microtubules in DJM-1 cells. In immunoprecipitation assays, SEPT1 and SEPT5 were found to form a complex in DJM-1 cells, whereas SEPT9, SEPT11 and SEPT14 formed a distinct complex with other septins including SEPT7, SEPT8 and SEPT10, in which SEPT5 was not included. When SEPT1 was silenced in DJM-1 cells, cell spreading was inhibited. These results suggest that SEPT1 may participate in cell-cell and/or cell-substrate interaction in DJM-1 and exert its function in a coordinated manner with other septins.

Biochemical and Morphological Characterization of a Neurodevelopmental Disorder-Related Mono-ADP-Ribosylhydrolase, MACRO Domain Containing 2

“…A rabbit polyclonal antibody (anti-MacroD2) was generated and affinity-purified on a column to which the antigen had been conjugated. Polyclonal rabbit antibodies against a cytoskeleton-related protein, Sept11 (anti-Sept11) [16] and myc-tag [17] were prepared as described. The following mouse monoclonal antibodies were used; anti-GFP (Medical and Biological Laboratories, Nagoya, Japan), anti-myc 9E10 [18], antiTau-1 (Millipore, Temecula, CA, USA), anti-MAP2 (Sigma-Aldrich, St Louis, MO, USA), anti-GFAP (Sigma-Aldrich), anti-synaptophysin (Progen Biotechnik, Heidelberg, Germany), and anti-PSD95 (Abcam, Tokyo, Japan).…”

Septin Mutations in Human Cancers

“…While SEPT2/7 promote the cell migration and invasion of breast cancer cells, SEPT7 appears to have the opposite role in gliomas (Jiang et al, 2014; Zhang et al, 2016). Over-expression of other septins such as SEPT1 has been suggested to promote the migration of skin cancer cells (Mizutani et al, 2013). …”

“…The organization and contractile properties of actin-myosin filaments are modulated by septins, which cross-link and bend actin filaments into functional structures such as the cytokinetic contractile ring, the actin stress fibers that power cell migration, and cellular protrusions such as filopodia, pseudopodia and lamellipodia (Kinoshita et al, 1997, 2002; Joo et al, 2007; Kremer et al, 2007; Shankar et al, 2010; Hu et al, 2012; Mizutani et al, 2013; Dolat et al, 2014b; Mavrakis et al, 2014). Similarly, septins affect the organization, dynamics and post-translational modifications of the microtubule cytoskeleton, impacting the morphogenesis of epithelia and neurons (Spiliotis et al, 2008; Bowen et al, 2011; Ageta-Ishihara et al, 2013; Bai et al, 2013; Froidevaux-Klipfel et al, 2015).…”

СЕПТИНОВЫЕ КОМПЛЕКСЫ И?ДИНАМИКА ЦИТОСКЕЛЕТА, "Молекулярная Биология"

“…The exact size and composition of all vertebrate septin complexes has not been described yet; however, SEPT2/6/7/9, SEPT2/6/7, SEPT7/9/11 [29], SEPT3/5/7, and SEPT5/7/11 complexes were isolated from cell cultures [25, 30, 31]. Noncanonical complexes composed of subunits of the same group, such as SEPT2/5/6/7, SEPT4/5/8, SEPT4/14, SEPT2/5, and SEPT1/5, have also been described [32–37], but their functions are currently unknown.…”