Mutations in the @entity5 suppressor gene @entity1412 ( @entity1412 ) are early and critical events in the development of @entity694 . In the absence of functional @entity1412 , @entity12401 is not degraded in the cytoplasm and can be transported to the nucleus and turn on transcription of several genes, including the gap junction protein @entity16899 . @entity1412 also stabilizes microtubules and regulates microtubule polymerization. Changes in Wnt signalling and microtubule function are reported to affect the connexin level. To study the effect of heterozygous @entity1412 mutation we examined gap junctional intercellular communication (GJIC) in IMCE (Immorto-Min colonic epithelium) cells with one mutated @entity1412 allele and in YAMC (Young adult @entity19 colon) cells with normal @entity1412 function. IMCE cells had only half the GJIC level compared with YAMC cells. RT-PCR showed that both YAMC and IMCE cells express a common complement of seven connexin genes ( @entity43146 , @entity70370 , @entity32905 , @entity16898 , @entity11404 , @entity17704 and @entity11405 ), with an additional @entity70371 gene expression in YAMC cells. We found that the @entity11404 level was correspondingly lower in IMCE cells as detected by western blotting and immunofluorescence. There were no differences in the level or localization of @entity12401 and the downstream gene @entity3112 between the cells, indicating no activation of the Wnt-signalling pathway in cells with one mutated @entity1412 allele. We also examined the microtubule polymerization rate, and IMCE cells had markedly slower microtubule polymerization than YAMC cells. Hence, it appears that mutation in one @entity1412 allele is sufficient to affect microtubule function, while inactivation of both wild-type @entity1412 alleles may be necessary for activation of Wnt signalling. Reduction in GJIC and @entity11404 level in IMCE cells may be caused by reduced @entity11404 transport as a result of alterations in microtubule function.

Cells heterozygous for the ApcMin mutation have decreased gap junctional intercellular communication and XXXX level, and reduced microtubule polymerization.

@entity16899 :: ('14609(Tax:10090)', 'Gene') :: ['connexin43'] @entity43146 :: ('14619(Tax:10090)', 'Gene') :: ['Cx26'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumour'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity70371 :: ('118446(Tax:10090)', 'Gene') :: ['Cx29'] @entity32905 :: ('225152(Tax:10090)', 'Gene') :: ['Cx39'] @entity70370 :: ('14620(Tax:10090)', 'Gene') :: ['Cx31'] @entity11404 :: ('14611(Tax:10090)', 'Gene') :: ['Cx43'] @entity12401 :: ('12387(Tax:10090)', 'Gene') :: ['beta-catenin'] @entity16898 :: ('14613(Tax:10090)', 'Gene') :: ['Cx40'] @entity1412 :: ('MESH:D011125', 'Disease') :: ['adenomatous polyposis coli', 'Apc'] @entity694 :: ('MESH:D003110', 'Disease') :: ['colon cancer'] @entity17704 :: ('14615(Tax:10090)', 'Gene') :: ['Cx45'] @entity3112 :: ('12550(Tax:10090)', 'Gene') :: ['E-cadherin'] @entity11405 :: ('14616(Tax:10090)', 'Gene') :: ['Cx50']
@entity16899 :: (14609(Tax:10090),Gene) :: ['connexin43']
