Comparative expression analysis of the murine palladin isoforms

Abstract

Palladin fulfils a crucial function as a molecular scaffold in organizing and stabilizing the actin cytoskeleton. At least four major palladin isoforms exist due to different promoter usage and alternative splicing: a 200-kDa isoform, a 140-kDa isoform, and two isoforms with a size of 90 -92 kDa. Here, we describe their expression during mouse development and in adult tissues. The 200-kDa isoform is predominantly expressed in developing heart and skeletal muscle. The 140-kDa isoform is expressed in various mesenchymal tissues, and also represents the major isoform of the brain. The 90 -92-kDa isoforms are almost ubiquitously expressed with the highest levels in smooth muscle-rich tissues. Immunohistochemical and immunofluorecence staining with an anti-200-kDa isoform-specific antiserum localizes the large isoform to the Z-discs of cardiac and skeletal muscle cells. Interestingly, the expression of this isoform is initiated and increasing during in vitro differentiation and fusion of C2C12 myoblasts, suggesting that the 200-kDa palladin isoform may play a scaffolding role during sarcomeric organization. Developmental Dynamics 237: 3342-3351, 2008.

Developmental effects of tobacco smoke exposure during human embryonic stem cell differentiation are mediated through the transforming growth factor-β superfamily member, Nodal

“…Using cutoffs for fold-change in gene expression greater than 1.5, and significance of p<0.05, we identified genes that could be ascribed to the development of specific physiological systems (Table 1). This identified gene products important in the development of tissues arising from mesoderm (e.g., AKT2, annexin A1, BCL3, interleukin-23, PI3 kinase, cyclooxygenase-2, SOCS1, and STAT5B (Boniface et al, 2008; Chen et al, 2003; Damazo et al, 2007; Diao et al, 2009; Palmer and Chen, 2008; Peng et al, 2003; Ramjaun and Downward, 2007; Trenerry et al, 2011)), as well as transcripts fundamental to cellular development across germ layers (e.g., CREB1, integrin β1, focal adhesion kinase, neurofibromin 1, palladin (Chatzizacharias et al, 2010; Diwakar et al, 2008; Faraldo et al, 2000; Ingram et al, 2002; Jin, 2011; Kossler et al, 2011; Leone et al, 2011; Luo et al, 2005; Potocnik, 2000; Sengbusch et al, 2002; Wang and Moser, 2008; Yashpal et al, 2005; Zubenko and Hughes, 2010)). The systems with the highest numbers of differentially expressed genes in tobacco-exposed tissues included the hematological, musculoskeletal, and cardiovascular systems, all of which have mesodermal origins (Fig.…”

Isoform-Specific Upregulation of Palladin in Human and Murine Pancreas Tumors

“…a “nested gene”. There are three major palladin isoforms that arise from alternative start sites (85–90, 140 and 200 kDa) and multiple minor isoforms that result from alternative splicing [10], [17], [18], [19]. This rich diversity of isoforms raises the possibility that human cells may express palladin variants that are not detected by all antibodies, which could be the cause of previous conflicting results.…”

The Actin Associated Protein Palladin Is Important for the Early Smooth Muscle Cell Differentiation

“…Overexpression of palladin induces strong stress fibers in cultured cells[23]. Palladin is highly expressed in smooth muscle and we and others have previously shown it is important in organization of the SMC cytoskeleton and in regulating contraction [24], [25]. Moreover, we recently published results showing that palladin knockout embryonic stem cells (ESC) exhibit impaired differentiation into SMC in a embryoid body (EB) SMC differentiation model system [26].…”