Identification of ICIS-1, a new protein involved in cilia stability.
Cilia are specialized organelles that exert critical functions in numerous organisms, including that of cell motility, fluid transport and protozoan locomotion. Ciliary architecture and function strictly depend on basal body formation, migration and axoneme elongation. Numerous ultrastructural studies have been undertaken in different species to elucidate the process of ciliogenesis. Recent analyses have led to identification of genes specifically expressed in ciliated organisms, but most proteins involved in ciliogenesis remain uncharacterized. Using human nasal epithelial cells capable of ciliary differentiation in vitro, differential display was carried out to identify new proteins associated with ciliogenesis. We isolated a new gene, ICIS-1 (Involved in CIlia Stability-1), upregulated during mucociliary differentiation. This gene is localized within the TGF-beta1 promoter and is ubiquitously expressed in human tissues. Functional analyses of gene expression inhibition by RNA interference in Paramecium tetraurelia indicated that the ICIS-1 homologue interfered with cilia stability or formation. These findings demonstrate that ICIS-1 is a new protein associated with ciliated cells and potentially related to cilia stability.
Ponsard
Cecile
C
Laboratoire de Cytophysiologie et Toxicologie Cellulaire, Universite Paris 7, France.
Skowron-Zwarg
Marie
M
Seltzer
Virginie
V
Perret
Eric
E
Gallinger
Julia
J
Fisch
Cathy
C
Dupuis-Williams
Pascale
P
Caruso
Nathalie
N
Middendorp
Sandrine
S
Tournier
Frederic
F
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D002478:Cells, Cultured; D002923:Cilia / Q000502:physiology*; D006801:Humans; D008969:Molecular Sequence Data; D009297:Nasal Mucosa / Q000166:cytology; D016805:Paramecium tetraurelia / Q000235:genetics; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D011506:Proteins / Q000145:classification / Q000235:genetics* / Q000502:physiology*; D015800:Protozoan Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D034622:RNA Interference; D017385:Sequence Homology; D014018:Tissue Distribution; D053773:Transforming Growth Factor beta1 / Q000235:genetics
D011506:Proteins; D015800:Protozoan Proteins; D053773:Transforming Growth Factor beta1