title: Expression of the DNA repair enzyme, photolyase, in developmental tissues and larvae, and in response to ambient UV-R in the Antarctic sea urchin Sterechinus neumayeri.
abstract: Gene expression of the DNA repair enzyme, photolyase (E.C. 4.1.99.3) was examined in the gonads, eggs, embryos and larval stages of the Antarctic sea urchin, Sterechinus neumayeri. Partial sequencing of the gene revealed two highly conserved regions, including a 300 bp region representing the binding site for the cofactor flavin adenine dinucleotide. The second 1200 bp region, likely representing a second light-harvesting cofactor binding site, was identified in a second sea urchin species, Strongylocentrotus frascicanus. Probes for photolyase were developed from the shorter sequence, and expression in sea urchin developmental tissue and stages, and in response to in situ exposure to ultraviolet radiation was quantified using PCR and RT-qPCR, with concentrations of photolyase normalized to actin concentrations. Photolyase was expressed in all tissues and developmental stages examined. In controlled field-based experiments in McMurdo Sound, Antarctica, we found evidence of both constitutive expression of photolyase and induction in response to in situ exposure of embryos to UV-R. Induction of photolyase was observed in response to greater ambient UV-R (such as shallower water depths or sea ice-free regions).
authors.affiliation: Department of Marine Science, University of Otago, Dunedin, New Zealand.
authors.forename: Nikolas
authors.initials: N
authors.lastname: Isely
authors.forename: Miles
authors.initials: M
authors.lastname: Lamare
authors.forename: Craig
authors.initials: C
authors.lastname: Marshall
authors.forename: Mike
authors.initials: M
authors.lastname: Barker
mesh_terms: D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D004260:DNA Repair; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000378:metabolism*; D007814:Larva / Q000201:enzymology*; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012617:Sea Urchins; D012689:Sequence Homology, Nucleic Acid; D014466:Ultraviolet Rays
chemical_list: D017931:DNA Primers; D004255:Deoxyribodipyrimidine Photo-Lyase