Cloning, characterization, and expression of human LIG1.
Growth factor receptors are frequently amplified and over-expressed in various human cancers. Recently, a Drosophila cell surface protein, Kekkon-1, was found to participate in an epidermal growth factor (EGF) driven negative feedback loop. Kekkon-1 is induced by EGF, binds to the EGF-receptor, and inhibits receptor-mediated signaling. Here, we have searched for human genes with homologies to Kekkon-1 and identified human LIG1. The gene is the human homologue of mouse Lig-1 and is located on chromosome band 3p14, a region frequently deleted in various human cancers. It is predicted to encode a transmembrane cell-surface protein with extracellular leucine-rich repeats and immunoglobulin-like domains. LIG1 mRNA was detected in all tissues analyzed. The highest and lowest relative expression levels were found in brain and spleen, respectively, and differed by more than 200-fold. Taken together, our data are compatible with a role for LIG1 as a growth and tumor suppressor in human tissues.
Nilsson
J
J
Department of Radiation Sciences, Umeå University, Umeå, SE-90187, Sweden.
Vallbo
C
C
Guo
D
D
Golovleva
I
I
Hallberg
B
B
Henriksson
R
R
Hedman
H
H
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D002893:Chromosomes, Human, Pair 3; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000032:analysis / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D007621:Karyotyping; D008562:Membrane Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D017385:Sequence Homology; D014018:Tissue Distribution
D018076:DNA, Complementary; C484445:LRIG1 protein, human; D008562:Membrane Glycoproteins