title: Two polymorphic residues account for the differences in DNA binding and transcriptional activation by NF-κB proteins encoded by naturally occurring alleles in Nematostella vectensis.
abstract: The NF-κB family of transcription factors is activated in response to many environmental and biological stresses, and plays a key role in innate immunity across a broad evolutionary expanse of animals. A simple NF-κB pathway is present in the sea anemone Nematostella vectensis, an important model organism in the phylum Cnidaria. Nematostella has previously been shown to have two naturally occurring NF-κB alleles (Nv-NF-κB-C and Nv-NF-κB-S) that encode proteins with different DNA-binding and transactivation abilities. We show here that polymorphic residues 67 (Cys vs. Ser) and 269 (Ala vs. Glu) play complementary roles in determining the DNA-binding activity of the NF-κB proteins encoded by these two alleles and that residue 67 is primarily responsible for the difference in their transactivation ability. Phylogenetic analysis indicates that Nv-NF-κB-S is the derived allele, consistent with its restricted geographic distribution. These results define polymorphic residues that are important for the DNA-binding and transactivating activities of two naturally occurring variants of Nv-NF-κB. The implications for the appearance of the two Nv-NF-κB alleles in natural populations of sea anemones are discussed.
authors.affiliation: Department of Biology, Boston University, Boston, MA 02215, USA.
authors.forename: Francis S
authors.initials: FS
authors.lastname: Wolenski
authors.forename: Sushil
authors.initials: S
authors.lastname: Chandani
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Stefanik
authors.forename: Ning
authors.initials: N
authors.lastname: Jiang
authors.forename: Emma
authors.initials: E
authors.lastname: Chu
authors.forename: John R
authors.initials: JR
authors.lastname: Finnerty
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Gilmore
mesh_terms: D000483:Alleles; D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D016328:NF-kappa B / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D017354:Point Mutation; D011110:Polymorphism, Genetic; D012615:Sea Anemones / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D015533:Transcriptional Activation
chemical_list: D004268:DNA-Binding Proteins; D016328:NF-kappa B