G-Protein Gα Functions with Abl Kinase to Regulate Actin Cytoskeletal Reorganization.

Heterotrimeric G-proteins are essential cellular signal transducers. One of the G-proteins, Gα, is critical for actin cytoskeletal reorganization, cell migration, cell proliferation, and apoptosis. Previously, we have shown that Gα is essential for both G-protein-coupled receptor and receptor tyrosine kinase-induced actin cytoskeletal reorganization such as dynamic dorsal ruffle turnover and cell migration.

Urine microRNA as potential biomarkers of autosomal dominant polycystic kidney disease progression: description of miRNA profiles at baseline.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is clinically heterogenic. Biomarkers are needed to predict prognosis and guide management. We aimed to profile microRNA (miRNA) in ADPKD to gain molecular insight and evaluate biomarker potential.

A novel long-range PCR sequencing method for genetic analysis of the entire PKD1 gene.

Genetic testing of PKD1 and PKD2 is useful for the diagnosis and prognosis of autosomal dominant polycystic kidney disease; however, analysis is complicated by the large transcript size, the complexity of the gene region, and the high level of gene variations. We developed a novel mutation screening assay for PKD1 by directly sequencing long-range (LR) PCR products. By using this method, the entire PKD1 coding region was amplified by nine reactions, generating product sizes from 2 to 6 kb, circumventing the need for specific PCR amplification of individual exons.

Autosomal dominant polycystic kidney disease: genetics, mutations and microRNAs.

Autosomal dominant polycystic kidney disease (ADPKD) is a common, monogenic multi-systemic disorder characterized by the development of renal cysts and various extrarenal manifestations. Worldwide, it is a common cause of end-stage renal disease. ADPKD is caused by mutation in either one of two principal genes, PKD1 and PKD2, but has large phenotypic variability among affected individuals, attributable to PKD genic and allelic variability and, possibly, modifier gene effects.

Novel method for genomic analysis of PKD1 and PKD2 mutations in autosomal dominant polycystic kidney disease.

Genetic testing of PKD1 and PKD2 is useful for diagnosis and prognosis of autosomal dominant polycystic kidney disease (ADPKD), particularly in asymptomatic individuals or those without a family history. PKD1 testing is complicated by the large transcript size, complexity of the gene region, and the extent of gene variations. A molecular assay was developed using Transgenomic's SURVEYOR Nuclease and WAVE Nucleic Acid High Sensitivity Fragment Analysis System to screen for PKD1 and PKD2 variants, followed by sequencing of variant gene segments, thereby reducing the sequencing reactions by 80%.

Common 8q24 sequence variations are associated with Asian Indian advanced prostate cancer risk.

Three sequence variations (rs1447295, rs16901979, and rs6983267) on 8q24 were recently shown to independently affect prostate cancer risk. Asian Indians have a low prostate cancer risk; however, in the absence of screening practices for the disease, most are diagnosed with metastatic prostate cancer. We evaluated the association of these single nucleotide polymorphisms (SNP) with advanced prostate cancer in 153 prostate cancer cases and 227 age-matched controls (northern India).

Analysis of the RNASEL/HPC1, and macrophage scavenger receptor 1 in Asian-Indian advanced prostate cancer.

Objectives: Prostate cancer (PC) varies widely by geographic location and ethnicity. American men have a high PC risk but most have localized disease. In contrast, Asian Indians have a low PC risk but most are diagnosed with metastatic disease.

A Rac-cGMP signaling pathway.

The small GTPase Rac and the second messenger cGMP (guanosine 3',5'-cyclic monophosphate) are critical regulators of diverse cell functions. When activated by extracellular signals via membrane signaling receptors, Rac executes its functions through engaging downstream effectors such as p21-activated kinase (PAK), a serine/threonine protein kinase. However, the molecular mechanism by which membrane signaling receptors regulate cGMP levels is not known.

G proteins G12 and G13 control the dynamic turnover of growth factor-induced dorsal ruffles.

Growth factors induce massive actin cytoskeletal remodeling in cells. These reorganization events underlie various cellular responses such as cell migration and morphological changes. One major form of actin reorganization is the formation and disassembly of dorsal ruffles (also named waves, dorsal rings, or circular ruffles).

The G protein G alpha(13) is required for growth factor-induced cell migration.

Heterotrimeric G proteins are critical cellular signal transducers. They are known to directly relay signals from seven-transmembrane G protein-coupled receptors (GPCRs) to downstream effectors. On the other hand, receptor tyrosine kinases (RTKs), a different family of membrane receptors, signal through docking sites in their carboxy-terminal tails created by autophosphorylated tyrosine residues.

Characterization of the interactions between the small GTPase RhoA and its guanine nucleotide exchange factors.

A novel spectrophotometric method to study the kinetics of the guanine nucleotide exchange factors-catalyzed reactions is presented. The method incorporates two coupling enzyme systems: (a). GTPase-activating protein which stimulates the intrinsic GTP hydrolysis reaction of small GTPases and (b).

Effect of Mg(2+) on the kinetics of guanine nucleotide binding and hydrolysis by Cdc42.

The biological activities of Rho family GTPases are controlled by their guanine nucleotide binding states in cell. Mg(2+) ions play key roles in guanine nucleotide binding and in preserving the structural integrity of GTPases. We describe here the kinetics of the interaction of GTP with the Rho family small GTPase Cdc42 in the absence and presence of Mg(2+).