title: Characterization of two POU transcription factor family members from the urochordate Oikopleura dioica.
abstract: Three POU domain containing transcription factors have been cloned from the urochordate Oikopleura dioica. Phylogenetic analysis showed that two of these (OctA1 and OctA2) are closely related members of the class II POU domain family, and one (OctB) is a member of the class III POU domain family. All three transcription factors contained a highly conserved bipartite DNA-binding POU domain with POU specific and POU homeodomains, separated by a linker region. All three proteins were shown to bind specifically to the canonical octamer motif, ATGCAAAT. The ability of these factors to drive transcription from an octamer-containing reporter construct was assessed in vertebrate B lymphocyte cell lines. Both OctA1 and OctA2 drove transcription in murine and catfish B cell lines, however, OctB did not increase the level of transcription above background levels. It is concluded that Oct transcription factors capable of functioning in a similar fashion to vertebrate Oct1/2 were present at the phylogenetic level of the urochordates.
authors.affiliation: Sars International Centre for Marine Molecular Biology, Bergen, Norway.
authors.forename: Pauline M
authors.initials: PM
authors.lastname: Cupit
authors.forename: Mara L
authors.initials: ML
authors.lastname: Lennard
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Hikima
authors.forename: Greg W
authors.initials: GW
authors.lastname: Warr
authors.forename: Charles
authors.initials: C
authors.lastname: Cunningham
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D001483:Base Sequence; D002397:Catfishes; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D050809:POU Domain Factors / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014561:Urochordata / Q000235:genetics* / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D050809:POU Domain Factors; D011994:Recombinant Proteins