Editors' ChoiceMAP Kinase

Map kinase: P44 Has a Role of Its Own

Science's STKE  16 Nov 1999:
Vol. 1999, Issue 8, pp. tw5
DOI: 10.1126/stke.1999.8.tw5

The p44 mitogen-activated protein kinase (MAPK) and its isoform, p42 MAPK, participate in signaling in response to many different stimuli in a broad range of cell types, and it has not been clear whether each has specific functions or whether the two enzymes can compensate for one another. Pagès et al. describe the phenotype of mice lacking the p44 MAPK. Mice lacking p44 MAPK were viable and fertile, but had specific defects in maturation and proliferation of thymocytes. Although p44 MAPK is not an essential protein for life (probably because the remaining p42 MAPK prevents complete loss of function), it appears to have a distinct biological role in the development of the immune system.

Pagès, G., Guérin, S., Grall, D., Bonino, F., Smith, A., Anjuere, F., Auberger, P., and Pouysségur, J. (1999) Defective thymocyte maturation in p44 MAP kinase (Erk 1) knockout mice. Science 286: 1374-1377. [Abstract] [Full Text]