Three neurexin (NRXN) genes are known in humans, each transcribed from two promoters and extensively spliced at five canonical positions, thus generating thousands of isoforms. For NRXN3, only neurona Show more
Three neurexin (NRXN) genes are known in humans, each transcribed from two promoters and extensively spliced at five canonical positions, thus generating thousands of isoforms. For NRXN3, only neuronal expression was reported so far. We reported here on the expression of NRXN3 in additional tissues (lung, pancreas, heart, placenta, liver, and kidney) and on the identification and characterization of heart-specific splicing variants of NRXN3. Cardiac isoforms of NRXN3 probably participate in a complex involving dystroglycan and proteins of extracellular matrix, involved in intercellular connections. Show less
The mitogen-activated protein kinase (MAPK) signaling cascade is one of the most important mechanisms for the cytoplasmic transduction of extracellular signals. We report the chromosomal localization Show more
The mitogen-activated protein kinase (MAPK) signaling cascade is one of the most important mechanisms for the cytoplasmic transduction of extracellular signals. We report the chromosomal localization of the human MEK1, MEK3, MEK4 and MEKK5 genes, involved in the MAPK cascade. Using radiation hybrid mapping, MEK1 was assigned to chromosome 15q22.1 --> q22.33, MEK3 to chromosome 17q11.2, MEK4 to chromosome 17p12, and MEKK5 to chromosome 6q22.33. Show less