A NOVEL CDNA WITH HOMOLOGY TO AN RNA-POLYMERASE-II ELONGATION-FACTOR MAPS TO HUMAN-CHROMOSOME 5Q31 (TCEB1L) AND TO MOUSE CHROMOSOME-11 (TCEB1L)

Few of the auxiliary factors that assist RNA polymerase II in the proc ess of mRNA chain elongation have been identified. We have isolated a novel cDNA, Tceb1l, from mouse and human sources that encodes a 163-am ino-acid protein and shows a significant level of identity with a rece ntly identified RNA polymerase II transcription elongation factor, p15 . Tceb1l is highly conserved throughout vertebrates and maps to mouse chromosome 11 and to the syntenic region of human chromosome 5q31. Tce b1l shows a restricted pattern of expression in the early mouse embryo , where it is absent from the neurectoderm; later Tceb1l is expressed in the caudal region of the neural tube, followed by widespread expres sion in many tissues, including the brain and spinal cord. These obser vations are consistent with Tceb1l being an RNA polymerase II elongati on factor and suggest that Tceb1l/p15-like peptides may be a new famil y of proteins that influence RNA elongation. (C) 1995 Academic Press, Inc.