Molecular cloning and expression of two types of rabbit beta-galactoside alpha 1,2-fucosyltransferase.
Two DNA clones encoding rabbit beta-galactoside alpha 1,2-fucosyltransferase (RFT-I and RFT-II) have been isolated from a rabbit genomic DNA library. The DNA sequences revealed open reading frames coding for 373 (RFT-I) and 354 (RFT-II) amino acids, respectively. The deduced amino acid sequences of RFT-I and RFT-II showed 56% identity with each other, and that of RFT-I showed 80% identity with that of human H blood type alpha 1,2-fucosyltransferase. Northern blot analysis of embryo and adult rabbit tissues revealed that the RFT-I gene was expressed in adult brain, and that the RFT-II gene was expressed in salivary and lactating mammary glands. The identities of these enzymes were confirmed by constructing recombinant fucosyltransferases in which the N-terminal part including the cytoplasmic tail and signal anchor domain was replaced with the immunoglobulin signal peptide sequence. RFT-I expressed in COS-7 cells exhibited similar transferase activity to that of human H blood type alpha 1,2-fucosyltransferase. RFT-II expressed in COS-7 cells showed higher affinity for type 1 (Gal beta 1,3GlcNAc) and type 3 (Gal beta 1,3GalNAc) acceptors than type 2 (Gal beta 1,4GlcNAc) ones, which suggested that RFT-II was a putative secretor-type alpha 1,2-fucosyltransferase.
Hitoshi
S
S
Molecular Glycobiology, Frontier Research Program, Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
Kusunoki
S
S
Kanazawa
I
I
Tsuji
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002240:Carbohydrate Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA; D005647:Fucosyltransferases / Q000235:genetics* / Q000378:metabolism; D007527:Isoenzymes / Q000235:genetics*; D008969:Molecular Sequence Data; D011817:Rabbits; D000097631:Galactoside 2-alpha-L-fucosyltransferase
D004247:DNA; D005647:Fucosyltransferases; D007527:Isoenzymes; D000097631:Galactoside 2-alpha-L-fucosyltransferase