Dystroglycan is a receptor responsible for crucial interactions between ext
racellular matrix and cytoplasmic space. We provide the first evidence that
dystroglycan is truncated, In HC11 normal murine and the 184B5 non-tumorig
enic mammary human cell lines, the expected beta -dystraglycan 43 kDa band
was found but human breast T47D, BT549, MCF7, colon HT29, HCT116, SW620, pr
ostate DU145 and cervical HeLa cancer cells expressed an anomalous approxim
ate to 31 kDa beta -dystroglycan band, alpha -Dystroglycan was udetectable
in most of the cell lines in which beta -dystroglycan was found as a approx
imate to 31 kDa species, An anomalous approximate to 31 kDa beta -dystrogly
can band was also observed in N-methyl-N-nitrosurea-induced primary rat mam
mary tumours, Reverse transcriptase polymerase chain reaction experiments c
onfirmed the absence of alternative splicing events and/or expression of ev
entual dystroglycan isoforms, Using protein extraction procedures at low- a
nd high-ionic strength, we demonstrated that both the 43 kDa and approximat
e to 31 kDa beta -dystroglycan bands harbour their transmembrane segment. (
C) 2000 Federation of European Biochemical Societies, Published by Elsevier
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