Identification of a Novel Structural Variant of the α6 Integrin

Tracy L. Davis, Isaac Rabinovitz, Bernard W. Futscher, Martina Schnölzer, Friederike Burger, Yuangang Liu, Molly Kulesz-Martin, Anne E. Cress

Research output: Contribution to journalArticlepeer-review

45 Scopus citations


The α6 integrin is a 140-kDa (nonreduced) laminin receptor. We have identified a novel 70-kDa (nonreduced) form of the α6 integrin called α6p for the latin word parvus, meaning small. The variant was immunoprecipitated from human cells using four different α6-specific monoclonal antibodies but not with α3 or α5 antibodies. The α 6p integrin contained identical amino acid sequences within exons 13-25, corresponding to the extracellular "stalk region" and the cytoplasmic tail of the α6 integrin. The light chains of α6 and α6p were identical as judged by α6A-specific antibodies and electrophoretic properties. The α6p variant paired with either β1 or β4 subunits and was retained on the cell surface three times longer than α6. Reverse transcription/polymerase chain reaction analysis revealed a single polymerase chain reaction product. The α6p variant was found in human prostate (DU145H, LnCaP, PC3) and colon (SW480) cancer cell lines but not in normal prostate (PrEC), breast cancer (MCF-7), or lung cancer (H69) cell lines or a variant of a prostate carcinoma cell line (PC3-N). Protein levels of α6p increased 3-fold during calcium-induced terminal differentiation in a normal mouse keratinocyte model system. A novel form of the α6 integrin exists on cell surfaces that contains a dramatically altered extracellular domain.

Original languageEnglish (US)
Pages (from-to)26099-26106
Number of pages8
JournalJournal of Biological Chemistry
Issue number28
StatePublished - Jul 13 2001

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Identification of a Novel Structural Variant of the α6 Integrin'. Together they form a unique fingerprint.

Cite this