Journal Article

The <i>TSC1</i> gene product, hamartin, negatively regulates cell proliferation

Angelina Miloloza, Margit Rosner, Mark Nellist, Dicky Halley, Gerhard Bernaschek and Markus Hengstschläger

in Human Molecular Genetics

Volume 9, issue 12, pages 1721-1727
Published in print July 2000 | ISSN: 0964-6906
Published online July 2000 | e-ISSN: 1460-2083 | DOI:
The TSC1 gene product, hamartin, negatively regulates cell proliferation

Show Summary Details


Tuberous sclerosis is an autosomal dominant hereditary disease caused by mutations in either the TSC1 or the TSC2 tumor suppressor gene. The TSC1 gene on chromosome 9q34 encodes a 130 kDa protein named hamartin, and the TSC2 gene on chromosome 16p13.3 codes for tuberin, a 200 kDa protein. Here we show that expression of hamartin, assayed by immunoblot analyses, is high in G0-arrested cells and hamartin is expressed throughout the entire ongoing cell cycle. An interaction of hamartin and tuberin can be detected in every phase of the cell cycle. Ectopic expression of high levels of hamartin attenuates cellular proliferation. We provide evidence that this effect could depend on a coiled-coil region earlier proposed to be involved in binding of hamartin to tuberin. Further investigations revealed that hamartin affects cell proliferation via deregulation of G1 phase. Our data have a clear impact on understanding the role of hamartin during development of this disease.

Journal Article.  5130 words.  Illustrated.

Subjects: Genetics and Genomics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.