Disease relevance of Xksy

• This mutation prevented Ras-mediated but not tyrosine kinase-mediated enzymatic activation of Raf-1 in the baculovirus/Sf9 expression system [1].
• Alignment persisted in the presence of gadolinium chloride, a blocker of stretch-activated calcium channels, the G protein inhibitor pertussis toxin, the protein tyrosine kinase inhibitor genistein, the protein kinase A and G inhibitor HA1004, the protein kinase A inhibitor KT5720and the protein kinase G inhibitor KT5823 [2].

High impact information on Xksy

• These data indicate that the control system, which monitors the state of DNA replication, modulates the function of the tyrosine kinase by a phosphorylation/dephosphorylation mechanism, ensuring that mitosis occurs only when S phase is complete [3].
• Coupling of mitosis to the completion of S phase in Xenopus occurs via modulation of the tyrosine kinase that phosphorylates p34cdc2 [3].
• Fibroblast growth factors (FGFs) signal through high-affinity tyrosine kinase receptors to regulate a diverse range of cellular processes, including cell growth, differentiation and migration, as well as cell death [4].
• The microtubule plus end tracking protein Orbit/MAST/CLASP acts downstream of the tyrosine kinase Abl in mediating axon guidance [5].
• Active calpain alters the balance between tyrosine kinase and phosphatase activities in filopodia, resulting in a net decrease in tyrosine phosphorylation, which mediates both filopodial stabilization and reduced lamellipodial protrusion [6].

Biological context of Xksy

• These findings suggest that Xksy may play an important role in growth, differentiation and the accurate migration of cells during embryogenesis and early neural development [7].
• Whole-mount in situ hybridization analyses revealed that expression of Xksy is localized to the nervous system of the tadpole stage, including origins of sensory organs and branchial arches [7].
• Moreover, okadaic acid and caffeine, which uncouple the dependence of mitosis on the completion of S phase, increase unphosphorylated p34cdc2 by attenuating tyrosine kinase function [3].
• In addition, it suggests that cell surface tyrosine kinase activity may play an important role in regulating resumption of the cell cycle [8].
• Our results demonstrate that the purified, isolated SH2 domains retain structural and functional specificity and that Xenopus oocytes constitute an useful biological system to analyse their functional role in tyrosine kinase signaling pathways [9].

Anatomical context of Xksy

• Agrin activates the transmembrane tyrosine kinase MuSK to mediate acetylcholine receptor (AChR) clustering at the neuromuscular junction (NMJ) [10].
• Analysis of mutant receptor proteins expressed in Xenopus oocytes indicates that all but one have elevated tyrosine kinase activity relative to their wild-type counterparts [11].
• Microinjection of Xenopus embryos with RNA encoding mutant receptors with elevated tyrosine kinase activity results in ligand-independent induction of mesoderm in animal pole explants [11].
• Native Kir2.1 channels in rat basophilic leukocytes were affected by manipulation of the TK and protein tyrosine phosphatase activity in a qualitatively similar manner [12].
• Focal adhesion kinase is a recently characterized tyrosine kinase that is concentrated at focal contacts in cultured cells [13].

Associations of Xksy with chemical compounds

• Xenopus MAP kinase activator is a serine/threonine/tyrosine kinase activated by threonine phosphorylation [14].
• When cultures were subjected to E fields in the presence of a tyrosine kinase inhibitor, tyrphostin RG-50864, cathodal AChR clustering was abolished with a half maximal inhibitory dosage of 50 microM [15].
• RG50864 also inhibited PY accumulation at bead contacts, providing evidence for tyrosine kinase activation in response to the bead stimulus [16].
• The sperm-dependent phosphorylation was sensitive to the tyrosine kinase inhibitors PP2 and genistein [17].
• These results suggest that Xp95 is an element in a tyrosine kinase signaling pathway that may be involved in progesterone-induced Xenopus oocyte maturation [18].

Analytical, diagnostic and therapeutic context of Xksy

• In contrast to the predominant expression of sky mRNA in the adult mammalian nervous system, Northern blot analysis showed ubiquitous expression of a single 5.2-kb Xksy mRNA in tissues of the adult Xenopus [7].
• Despite the Kir2.1 inhibition and endocytosis stimulated by tyrosine kinase activation, neither Western blotting nor (32)P labeling produced evidence for direct tyrosine phosphorylation of Kir2 [19].
• A 58-kDa protein was detected in Xenopus egg lysate by SDS-PAGE and immunoblotting with an antibody raised against adaptor protein Shc, a well known tyrosine kinase substrate in numerous biological events [20].
• Xenopus laevis and X. borealis were screened for tyrosine kinase genes using the polymerase chain reaction (PCR) and reverse transcriptase (RT)-PCR and 34 X. laevis and 23 X. borealis tyrosine genes were identified [21].
• A rapid bioassay for platelet-derived growth factor beta-receptor tyrosine kinase function [22].

References