Abstract
Claudins are a family of proteins involved in forming tight junctions between cells. Here we describe two forms of claudin-7 (CLDN-7), a full-length form of CLDN-7 with 211 amino-acid residues and a C-terminal truncated form with 158 amino-acid residues. These two forms of CLDN-7 are able to regulate the expression of a tissue-specific protein, the prostate-specific antigen (PSA), in the LNCaP prostate cancer cell line. We also found that the expression of CLDN-7 is responsive to androgen stimulation in the LNCaP cell line, suggesting that this protein is involved in the regulatory mechanism of androgen. Both forms of claudin-7 are expressed in human prostate, kidney and lung samples, and in most samples, the full-length form of claudin-7 was predominant. However, in some prostate samples from healthy individuals, the truncated form of claudin-7 is predominantly expressed. Our results demonstrated that unlike other claudins, CLDN-7 has both structural and regulatory functions, and the two forms of CLDN-7 may be related to cell differentiation in organ development.
MeSH terms
-
Adenocarcinoma / metabolism
-
Adenocarcinoma / pathology*
-
Amino Acid Sequence
-
Cell Line, Tumor / drug effects
-
Cell Line, Tumor / metabolism
-
Claudins
-
DNA, Complementary / genetics
-
Gene Expression Profiling
-
Gene Expression Regulation, Neoplastic / physiology*
-
Humans
-
Male
-
Membrane Proteins / biosynthesis
-
Membrane Proteins / chemistry
-
Membrane Proteins / genetics
-
Membrane Proteins / physiology*
-
Molecular Sequence Data
-
Neoplasm Proteins / biosynthesis
-
Neoplasm Proteins / chemistry
-
Neoplasm Proteins / genetics
-
Neoplasm Proteins / physiology*
-
Organ Specificity
-
Prostate-Specific Antigen / biosynthesis*
-
Prostate-Specific Antigen / genetics
-
Prostatic Neoplasms / metabolism
-
Prostatic Neoplasms / pathology*
-
Protein Isoforms / chemistry
-
Protein Isoforms / physiology
-
Protein Structure, Tertiary
-
RNA, Messenger / biosynthesis
-
RNA, Neoplasm / biosynthesis
-
Recombinant Fusion Proteins / genetics
-
Recombinant Fusion Proteins / physiology
-
Structure-Activity Relationship
-
Subtraction Technique
-
Tight Junctions / physiology
-
Transfection
Substances
-
CLDN7 protein, human
-
Claudins
-
DNA, Complementary
-
Membrane Proteins
-
Neoplasm Proteins
-
Protein Isoforms
-
RNA, Messenger
-
RNA, Neoplasm
-
Recombinant Fusion Proteins
-
Prostate-Specific Antigen