Partial sequence homology of human myc oncogene protein to beta and gamma crystallins

Abstract

The human cellular myc gene is one of about 20 cellular oncogenes which code for a variety of proteins including protein kinases and growth factors [1]. The human gene is related to the avian myelocytomatosis leukaemia virus MC29 [2] and produces a binding protein which may be involved in regulation of gene expression [3] and cellular differentiation and proliferation [4]. The crystallins are proteins in the eye lens synthesised at different stages of cell differentiation and proliferation, and whose short range order is necessary for lens transparency [5,6]. Computer-based sequence comparisons show that beta Bp and gamma II crystallins, which show partial sequence homology and conservation of ‘Greek Key’ motives [7,8] are also partially homologous to two regions on the human myc protein, though this protein probably does not conserve the ‘Greek Key’ structural motives