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General Comment |
Pietas A,et al 2002 reported molecular cloning and characterization of the human S100A14 gene
encoding a novel member of the S100 family.
S100 proteins form a growing subfamily of proteins related by Ca2+-binding motifs to
the Efhand Ca2+-binding protein superfamily. By analyzing a human lung cancer cell
line subtraction cDNA library, we have identified and characterized a new member of
the human S100 family that we named S100A14 (GenBank acc. no. NM_020672). It
encodes a mRNA present in several normal human tissues of epithelial origin, with
the highest level of expression in colon. The full-length cDNA is 1067 nt in length,
with a coding region predicting a protein of 104 amino acids that is 68% homologous
to the S100A13 protein. The deduced amino acid sequence of the human S100A14
and its mouse homolog (identified as GenBank entry) contains two EF-hand
Ca2+-binding domains, a myristoylation motif, a glycosylation site, and several
potential protein kinase phosphorylation sites. The authors have mapped this gene to human
chromosome 1q21, within a region where at least 15 other S100 genes are tightly
clustered. A 3.2-kb genomic fragment containing the entire S100A14 was cloned and
sequenced. The gene is split into four exons and three introns spanning a total of 2165
bp of genomic sequence. We examined the intracellular distribution of the
epitope-tagged S100A14 protein in two human lung carcinoma cell lines and one
immortalized monkey cell line. Pronounced staining was observed in the cytoplasm,
suggesting an association with the plasma membrane and in the perinuclear area.Theres is also evidence for heterogenic expression of S100A14 in tumors,
demonstrating its overexpression in ovary, breast, and uterus tumors and
underexpression in kidney, rectum, and colon tumors, a pattern suggesting distinct
regulation with potentially important functions in malignant transformation.
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