Molecular cloning and genomic organization of a gene for luciferin-binding protein from the dinoflagellate Gonyaulax polyedra.
The circadian expressed luciferin-binding protein (LBP) gene from the marine bioluminescent alga Gonyaulax polyedra represents the first dinoflagellate gene that has been cloned and sequenced at both cDNA and genomic levels. Starting with a fragment from the 3'-end of the LBP cDNA that was found by immunoscreening of a cDNA library, genomic clones were obtained by the inverse polymerase chain reaction technique. Full-length cDNA clones were selected by screening a cDNA library by plaque hybridizations and by polymerase chain reaction amplifications. The LBP sequence has a 2004-nucleotide open reading frame coding for a protein of 668 amino acids (approximately 75 kDa). The reading frame and identity of the clone were confirmed by the sequence of an octapeptide obtained from a purified fragment of CNBr-treated LBP. A variant LBP cDNA was found to differ in sequence by approximately 11% at the DNA level. The untranslated regions of the mRNA are 111 nucleotides (5'-untranslated region) and 158 nucleotides (3'-untranslated region) long, respectively. The LBP gene contains no introns and exhibits certain features not typical for a eukaryotic gene. Its promoter does not include the typical TATA box within approximately 50 nucleotides upstream of the transcription start site, and the usual poly(A+) signal (AAUAAA) is not present on the end of the LBP mRNA. The copy number of the gene is very high (approximately 1000 copies/cell). However, the universal genetic code and conserved positions relevant for the translational apparatus are maintained.
Lee
D H
DH
Department of Cellular and Developmental Biology, Harvard University, Cambridge, Massachusetts 02138.
Mittag
M
M
Sczekan
S
S
Morse
D
D
Hastings
J W
JW
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D016054:DNA, Protozoan; D004141:Dinoflagellida / Q000235:genetics*; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000235:genetics*; D015183:Restriction Mapping
D002135:Calcium-Binding Proteins; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C065397:luciferin-binding protein, dinoflagellate