Publication Database

Molecular Cloning and Biochemical Characterization of a Truncated, Secreted Member of the Human Family of Ca2+-activated Cl- Channels (1999)

Art

Zeitschriftenartikel / wissenschaftlicher Beitrag

Autoren

Gruber, A D (WE 12)

Pauli, B U

Quelle

Biochimica et biophysica acta : BBA. Bioenergetics

Bandzählung: 1444

Heftzählung: 3

Seiten: 418 – 423

ISSN: 1879-2650

Sprache

Englisch

Verweise

Pubmed: 10095065

Kontakt

Institut für Tierpathologie

Robert-von-Ostertag-Str. 15
14163 Berlin
+49 30 838 62450
pathologie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

A novel family of chloride channel proteins has recently been discovered including two bovine (Lu-ECAM-1, bCLCA1), one murine (mCLCA1), and two human (hCLCA1 and hCLCA2) members. Here, we describe the cloning, expression, and molecular characterization of a truncated human homolog, tentatively named hCLCA3. It was cloned from a human spleen cDNA library and is expressed in numerous tissues including lung, trachea, spleen, thymus, and mammary gland as determined by reverse transcriptase-polymerase chain reaction. Unlike all previously known CLCA family members which consistently encode an approximately 125-kDa transmembrane protein that is cleaved to form a heterodimer of two proteins of approximately 90 and 35 kDa, the 3.6-kb hCLCA3 mRNA encodes a 37-kDa glycoprotein that corresponds to the N-terminal extracellular domain of its homologs. Moreover, when expressed in human embryonic kidney 293 or Chinese hamster ovary cells, this 37-kDa glycoprotein is secreted into the culture supernatant. These observations suggest that hCLCA3 is a structurally divergent member of the CLCA family of proteins and that it does not act as a channel protein but has distinct, yet unidentified functions.