C. elegans homolog of tailless regulates male gonadal migration

Cell migrations are vital for the development of multicellular organisms and require precise spatial and temporal regulation. Interestingly, the migratory cell itself undergoes change during its migration, so temporal development is an important consideration in examining its dynamic cell biology. We are studying the male linker cell, an individual cell in C. elegans that directs the development of the male gonad by carrying out a complex, long‐range migration. During the mid‐third larval stage, we observed the downregulation of one of two C. elegans netrin receptors, unc‐5 . We show that this downregulation is required for the linker cell to respond differentially to netrin, an extracellular matrix protein present along the ventral bodywall when turning. During the fourth larval stage, we observe changes in linker cell shape, the membrane localization of the Rac homology, MIG‐2, and the expression of a zinc metalloprotease, zmp‐1 . In an RNAi screen of 508 transcription factors, we identified nhr‐67 , the ortholog of the Drosophila tailless and vertebrate Tlx genes, to be required for normal linker cell migration. We show that nhr‐67/tailless/Tlx functions cell autonomously in the linker cell to execute each of the third and fourth larval stage changes described. We propose that a series of transcriptional regulators, like nhr‐67/tailless/Tlx , controls temporal subsets of the linker cell migration program.