MAST-like protein kinase IREH1 from Arabidopsis thaliana co-localizes with the centrosome when expressed in animal cells.

The similarity of IREH1 (Incomplete Root Hair Elongation 1) and animal MAST kinases was confirmed; IREH1cDNA was cloned while expressing in cultured animal cells co-localized with the centrosome. In mammals and fruit flies, microtubule-associated serine/threonine-protein kinases (MAST) are strongly involved in the regulation of the microtubule system. Higher plants also possess protein kinases homologous to MASTs, but their function and interaction with the cytoskeleton remain unclear.

Involvement of Inositol Biosynthesis and Nitric Oxide in the Mediation of UV-B Induced Oxidative Stress.

The involvement of NO-signaling in ultraviolet B (UV-B) induced oxidative stress (OS) in plants is an open question. Inositol biosynthesis contributes to numerous cellular functions, including the regulation of plants tolerance to stress. This work reveals the involvement of inositol-3-phosphate synthase 1 (IPS1), a key enzyme for biosynthesis of myo-inositol and its derivatives, in the response to NO-dependent OS in Arabidopsis.

Nitric oxide signalling via cytoskeleton in plants.

Nitric oxide (NO) in plant cell mediates processes of growth and development starting from seed germination to pollination, as well as biotic and abiotic stress tolerance. However, proper understanding of the molecular mechanisms of NO signalling in plants has just begun to emerge. Accumulated evidence suggests that in eukaryotic cells NO regulates functions of proteins by their post-translational modifications, namely tyrosine nitration and S-nitrosylation.

Immunohistochemical analysis of S6K1 and S6K2 expression in endometrial adenocarcinomas.

Aim: The aim of this study was to analyze the levels 70 kDa ribosomal protein S6 kinase 1 (S6K1) and 70 kDa ribosomal protein S6 kinase 2 (S6K2) expression and S6 ribosomal protein phosphorylation in endometrial adenocarcinomas.

Methods: S6K1/2 expression and phosphorylated ribosomal S6 protein (phS6) content have been detected in formalin fixed, paraffin embedded sections of 50 human endometrial adenocarcinomas with different grade of differentiation and in 13 normal endometrial tissues using immunohistochemical approach with following semiquantitative analysis.

Results: In normal endometrial epithelial cells both S6K1 and S6K2 were expressed on the low level.