Two related serine/threonine kinases, UNC-51-like kinase 1 and 2 (ULK1, ULK2), were discovered as mammalian homologs of the C. elegans gene UNC-51 in which mutants exhibited abnormal axonal extension and growth. Both share homology with the UNC-51 kinase from Caenorhabditis elegans and the APG1 kinase in yeast, which are involved in axonal extension and growth, and autophagy, respectively. ULK1 is an important protein in autophagy. It is part of the ULK1-complex, which is needed in early steps of autophagosome biogenesis.
