N. Itano et K. Kimata, EXPRESSION CLONING AND MOLECULAR CHARACTERIZATION OF HAS PROTEIN, A EUKARYOTIC HYALURONAN SYNTHASE, The Journal of biological chemistry, 271(17), 1996, pp. 9875-9878
We developed a mammalian transient expression system to isolate cDNA c
lones that determine hyaluronan expression. HAS(-), a mouse mammary ca
rcinoma mutant cell line, which is defective in hyaluronan synthase ac
tivity, was first established and used as a recipient for the expressi
on cloning, One cloned cDNA that overcame the deficiency was isolated,
The cDNA termed HAS contains an open reading frame of 1749 base pairs
encoding a new protein of 583 amino acids, Homology analysis of the a
mino acid sequence suggests that HAS protein is related to streptococc
al hyaluronan synthase and also to Xenopus laevis DG42 protein that wa
s found to be homologous to bacterial hyaluronan synthase. Expression
of HAS cDNA in HAS(-) cells complemented not only their mutant phenoty
pes such as deficient hyaluronan-matrix deposition but also hyaluronan
synthase activity itself, Therefore, HAS cDNA is responsible for the
activity of the hyaluronan synthase, a key enzyme of hyaluronan synthe
sis in eukaryotic cells.