A Unique Role for Nonmuscle Myosin Heavy Chain IIA in Regulation of Epithelial Apical Junctions

The integrity and function of the epithelial barrier is dependent on the apical junctional complex (AJC) composed of tight and adherens junctions and regulated by the underlying actin filaments. A major F-actin motor, myosin II, was previously implicated in regulation of the AJC, however direct evidence of the involvement of myosin II in AJC dynamics are lacking and the molecular identity of the myosin II motor that regulates formation and disassembly of apical junctions in mammalian epithelia is unknown. We investigated the role of nonmuscle myosin II (NMMII) heavy chain isoforms, A, B, and C in regulation of epithelial AJC dynamics and function. Expression of the three NMMII isoforms was observed in model intestinal epithelial cell lines, where all isoforms accumulated within the perijunctional F-actin belt. siRNA-mediated downregulation of NMMIIA, but not NMMIIB or NMMIIC expression in SK-CO15 colonic epithelial cells resulted in profound changes of cell morphology and cell-cell adhesions. These changes included acquisition of a fibroblast-like cell shape, defective paracellular barrier, and substantial attenuation of the assembly and disassembly of both adherens and tight junctions. Impaired assembly of the AJC observed after NMMIIA knock-down involved dramatic disorganization of perijunctional actin filaments. These findings provide the first direct non-pharmacological evidence of myosin II-dependent regulation of AJC dynamics in mammalian epithelia and highlight a unique role of NMMIIA in junctional biogenesis

SNP, insertion, and deletion calls made by GATK on panel of melanoma cell lines

VCF file was generated using GAT

1371AJM0009

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

1371AJM0007

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

1120AJM0002

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

1533AJM0008_bwa

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

1371AJM0010

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

1533AJM0004_bwa

Archive of BAM files generated from exome sequencing of 16 melanoma cell lines. Exome sequences were generated using a combination of Agilent and NimbleGen captures. Variant calls as well as insertion and deletion calls were made using GATK

Sample ID and coverage stats table

Table contains columns for mapping cell lines to exome files, as well as average coverage and quantification of bases that had a Phred quality score of 20 or better