C. Tiffoche et al., ISOLATION AND CHARACTERIZATION OF A CDNA CLONE ENCODING A PLEURODELESLECTIN, European journal of biochemistry, 213(3), 1993, pp. 901-907
A cDNA encoding a lectin secreted by the oviduct of Pleurodeles waltl
has been isolated and sequenced. The cDNA was identified by comparing
the N-terminal amino-acid sequence of the purified P. waltl lectin pol
ypeptides with the amino-acid sequence deduced from the cDNA. The two
chains of the mature protein can be encoded within a unique mRNA. Two
mRNA were also found in the oviduct extracts. However, they probably r
esult from differential polyadenylation events. The mRNA are strictly
localized in the anterior part of the oviduct and increase after estra
diol stimulation, two characteristics which have been previously demon
strated for the protein. P. waltl is known to possess a very high DNA
content (almost-equal-to 2 X 10(10) bp) but the aforementioned results
and Southern-blot experiments suggest a unique or a least a very low
gene-copy number for this protein. The amino-acid sequence of the P. w
altl lectin deduced from the cDNA sequence shows similarities with the
C-type carbohydrate-recognition domains of animal lectins as defined
by Drickamer [Drickamer, K. (1988) J. Biol. Chem. 263, 9557-9560]. Alt
hough it is regulated by estradiol, the P. waltl lectin amino-acid seq
uence shows a higher similarity with animal lectins involved in the de
fence of the organism than with those involved in reproduction and dev
elopment.