Novel Development Rescuing Factors (DRFs) Secreted by the Developing Dictyostelium Cells, That are Involved in the Restoration of a Mutant Lacking MAP-kinase ERK2

• DOI: 10.2108/zsj.21.829
• Publication Date: 2004-10-08T08:18:51Z
• Authors: Masatsune Tsujioka; Tatsuyoshi Yamamoto; Christopher R. Th...; Robert R. Kay; Mineko Maeda
• Keywords: Multicellular organism; Wild type

We found novel development rescuing factors (DRFs) secreted from developing Dictyostelium cells, by using a mutant (erkB−) which is missing MAP-kinase ERK2 as test strain for bioassay. The erkB− fails to undergo multicellular morphogenesis due impaired cAMP signaling. However, such developmental defect can be restored the presence of low-molecular weight DRFs that are wild-type cells. previously showed DIF-1 (Differentiation-Inducing Factor 1 stalk cells) possesses this activity, indicating newly discovered role DIF-1. Surprisingly, however, dmtA−, incapable synthesis still exerts strong inducing activity erkB−. After analysis HPLC fractions conditioned media prepared both wild type Ax2 and dmtA− strains revealed secrete at least two DRF activities with DIF-like mobility. these were not derived other DIFs DIF-2 DIF-3. Identification in study would provide insight into mechanism how act normal Dictyostelium.