p38 MAP kinase (MAPK), also called RK (1) or CSBP (2), is the mammalian orthologue of the yeast HOG kinase that participates in a signaling cascade controlling cellular responses to cytokines and stress (1-4). Four isoforms of p38 MAP kinase, p38a B, y (also known as ERK6 or SAPK3), and d (also known as SAPK4) have been identified. Similar to the SAPK/JNK pathway, p38 MAP kinase is activated by a variety of cellular stresses including osmotic shock, inflammatory cytokines, lipopolysaccharides (LPS), UV light, and growth factors (1-5). MKK3, MKK6, and SEK activate p38 MAP kinase by phosphorylation at Thr180 and Tyr182. Activated p38 MAP kinase has been shown to phosphorylate and activate MAPKAP kinase 2 (3) and to phosphorylate the transcription factors ATF-2 (5), Max (6), and MEF2 (5-8). SB203580 (4-(4-fluorophenyl)- 2-(4-methylsulfinylphenyl)-5-(4- pyridyl)imidazole) is a se- lective inhibitor of p38 MAPK. This compound inhibits the activation of MAPKAPK-2 by p38 and thereby phosphoryla- tion of HSP27 (9). SB203580 inhibits p38 catalytic activity by binding to the ATP binding pocket, but does not inhibit phosphorylation of p38 by upstream kinases (10).
The p38 MAPK Isoform Activation Antibody Sampler Kit provides an economical means to evaluate the activation status of individual isoforms of p38 MAPK through immunoprecipitation of the phosphorylated p38 MAPK followed by western blot using isoform specific antibodies. The kit includes enough primary and secondary antibodies to perform four western blot experiments with each antibody.
Each isoform-specific antibody in the p38 MAPK Isoform Activation Antibody Sampler Kit recognizes the appropriate isoform of p38 MAPK. The Phospho-p38 MAPK (Thr180/Tyr182) Rabbit mAb recognizes all four isoforms of p38 MAPK when phosphorylated at the specified sites.
p38a MAPK Pab (Rb x Hu): 1x40ul
p38b MAPK Mab (Rb x Hu): 1x40ul
p38g MAPK Pab (Rb x Hu): 1x40ul
p38d MAPK Mab (Rb x Hu): 1x40ul
Phospho-p38 MAPK (Thr180/Tyr182) Mab (Rb x Hu): 1x40ul
Anti-rabbit IgG, HRP-linked Antibody: 1x100ul
Storage and Stability:
May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.