High impact information on p38b

• The Drosophila p38 MAPK pathway is required during oogenesis for egg asymmetric development [1].
• Furthermore, they show that in addition to the well-characterized Ras/Raf/ERK MAPK pathway acting in the follicle cells, another related signaling cascade, the p38 MAPK pathway, is required in the germ line for correct axes determination [1].
• Expression of a dominant-negative D-p38b in the wing imaginal disc caused a decapentaplegic (dpp)-like phenotype and enhanced the phenotype of a dpp mutant [2].
• The fruit fly, Drosophila melanogaster, has two p38 genes, D-p38a and D-p38b [2].
• Inhibition of D-p38b function also caused the suppression of the wing phenotype induced by constitutively active Tkv (TkvCA) [2].

Biological context of p38b

• The results revealed that one of the functions of D-p38 is to attenuate antimicrobial peptide gene expression following exposure to lipopolysaccharide [3].
• p38 mitogen-activated protein kinase can be involved in transforming growth factor beta superfamily signal transduction in Drosophila wing morphogenesis [2].
• In our previous report, it was proposed that P. aeruginosa secreting ExoS, upon infection, shuts down host cell survival signal pathways by inhibiting ERK1/2 and p38 activation, and it activates proapoptotic pathways through activation of JNK1/2, leading ultimately to cytochrome c release and activation of caspases [4].
• However, unlike mammalian p38 MAPK, the addition of lipopolysaccharide (LPS) did not significantly affect the phosphorylation of Dp38 in the LPS-responsive l(2)mbn cell line [5].

Anatomical context of p38b

• Dp38 was rapidly tyrosine 186-phosphorylated in response to osmotic stress, heat shock, serum starvation, and H2O2 in Drosophila l(2)mbn and Schneider cell lines [5].

Associations of p38b with chemical compounds

• Pre-treatment of Schneider cells with inhibitors of PKC, PP 1/2A, p38 MAPK, JNK and proteasomes resulted in the inhibition of morphological differentiation induced by NCS [6].
• HU-induced differentiation was inhibited upon pretreatment of cells with chemical inhibitors of PP 1/2A, p38 MAPK, JNK, and proteasome [7].
• Following osmotic stress, tyrosine 186-phosphorylated forms of Dp38 MAPK were detected exclusively in nuclear regions of Schneider cells [5].

Other interactions of p38b

• Ectopic expression of dMLK either in Drosophila S2 or in mammalian HEK293 cells leads to activation of JNK, p38 and extracellular signal regulated kinase (ERK) pathways [8].
• Activating transcription factor (ATF)-2 is a member of the ATF/cAMP response element-binding protein family of transcription factors, and its trans-activating capacity is enhanced by stress-activated protein kinases such as c-Jun NH(2)-terminal kinase (JNK) and p38 [9].
• Drosophila activating transcription factor-2 is involved in stress response via activation by p38, but not c-Jun NH(2)-terminal kinase [9].

Analytical, diagnostic and therapeutic context of p38b

• These results demonstrate that p38, in addition to its role as a transducer of emergency stress signaling, may function to modulate Dpp signaling [2].
• The cDNA sequence analysis showed that this Drosophila kinase is a homologue of mammalian p38 MAPK and the yeast HOG1 gene and thus was referred to as Dp38 [5].

References