Sperm-specific glyceraldehyde-3-phosphate dehydrogenase is expressed in melanoma cells

• Published in: Biochemical and biophysical research communications 2012-10, Vol.427 (3), p.649-653
• Main Authors: Sevostyanova, Irina A., Kulikova, Kseniya V., Kuravsky, Mikhail L., Schmalhausen, Elena V., Muronetz, Vladimir I.
• Format: Article
• Language: English
• Subjects: Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) - genetics; HEK293 Cells; HL-60 Cells; Humans; Jurkat Cells; Male; Melanoma; Melanoma - enzymology; RNA, Messenger - genetics; Sperm-specific glyceraldehyde-3-phosphate dehydrogenase; Spermatozoa - enzymology; Сancer/testis associated genes
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2012.09.115

► Melanoma cells were assayed for expression of sperm-specific glycolytic enzyme GAPDS. ► GAPDS fragment lacking N-terminal amino acid sequence is revealed in melanoma cells. ► The revealed GAPDS species form hybrid tetramers with somatic isoenzyme GAPD. ► Immunochemical staining of melanoma cells revealed native GAPDS in the cytoplasm. Sperm-specific glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDS) is normally expressed only in sperms, but not in somatic tissues. Analysis of the expression of GAPDS mRNA in different cancer cell lines shows that the content of GAPDS mRNA is enhanced in some lines of melanoma cells. The purpose of the study was to assay melanoma cells for the expression of protein GAPDS. Three different lines of melanoma cells were investigated. By data of Western blotting, all investigated cells contain a 37-kDa fragment of GAPDS polypeptide chain, which corresponds to the enzyme GAPDS lacking N-terminal amino acid sequence that attaches the enzyme to the cytoskeleton of the sperm flagellum. The results suggest that GAPDS is expressed in melanoma cells without N-terminal domain. The immunoprecipitation of proteins from melanoma cell extracts using rabbit polyclonal antibodies against native GAPDS allowed isolation of complexes containing 37-kDa subunit of GAPDS and full-length subunit of somatic glyceraldehyde-3-phosphate dehydrogenase (GAPD). The results indicate that melanoma cells express both isoenzymes, which results in the formation of heterotetrameric complexes. Immunocytochemical staining of melanoma cells revealed native GAPDS in the cytoplasm. It is assumed that the expression of GAPDS in melanoma cells may facilitate glycolysis and prevent the induction of apoptosis.