M. Bishr Omary

Learn More
Keratins are intermediate filament-forming proteins that provide mechanical support and fulfill a variety of additional functions in epithelial cells. In 1982, a nomenclature was devised to name the keratin proteins that were known at that point. The systematic sequencing of the human genome in recent years uncovered the existence of several novel keratin(More)
Pancreatic stellate cells (PaSCs) are myofibroblast-like cells found in the areas of the pancreas that have exocrine function. PaSCs are regulated by autocrine and paracrine stimuli and share many features with their hepatic counterparts, studies of which have helped further our understanding of PaSC biology. Activation of PaSCs induces them to proliferate,(More)
Sphingosylphosphorylcholine (SPC) is a naturally occurring bioactive lipid that is present in high density lipoproteins (HDL) particles and found at increased levels in blood and malignant ascites of patients with ovarian cancer. Here, we show that incubation of human epithelial tumour cells with SPC induces a perinuclear reorganization of intact keratin(More)
The gains that have been made in characterizing some of the keratin posttranslational modifications have helped answer some questions regarding these modifications and have generated an information base for asking additional refined questions in future studies. Highlights of where we believe we currently stand with regard to keratin posttranslational(More)
Intermediate filaments (IFs) are major components of the mammalian cytoskeleton. They are among the most abundant cellular phosphoproteins; their phosphorylation typically involves multiple sites at repeat or unique motifs, preferentially within the "head" or "tail" domains. Phosphorylation and dephosphorylation are essential for the regulation of IF(More)
Keratins make up the largest subgroup of intermediate filament proteins and represent the most abundant proteins in epithelial cells. They exist as highly dynamic networks of cytoplasmic 10-12 nm filaments that are obligate heteropolymers involving type I and type II keratins. The primary function of keratins is to protect epithelial cells from mechanical(More)
Keratin polypeptides 8 and 18 (K8/18) are intermediate filament proteins expressed preferentially in glandular epithelia. We describe the identification, by co-immunoprecipitation from normal human colonic tissues and cultured cell lines, of the 70-kDa heat shock protein (hsp) and its related heat shock cognate protein as K8/18-associated proteins (hsp/c).(More)
Simple epithelia express keratins 8 (K8) and 18 (K18) as their major intermediate filament proteins. We previously showed that several types of cell stress such as heat and virus infection result in a distinct hyperphosphorylated form of K8 (termed HK8). To better characterize K8/18 phosphorylation, we generated monoclonal antibodies by immunizing mice with(More)
Intermediate filaments (IFs) are cytoskeletal and nucleoskeletal structures that provide mechanical and stress-coping resilience to cells, contribute to subcellular and tissue-specific biological functions, and facilitate intracellular communication. IFs, including nuclear lamins and those in the cytoplasm (keratins, vimentin, desmin, neurofilaments and(More)