An emilin family extracellular matrix protein identified in the cochlear basilar membrane.
The precise movement of the cochlear basilar membrane (BM) stimulates the sensory hair cells during auditory transduction. However, the molecular composition of the BM that confers its specialized properties of support and elasticity is poorly understood. A differential screen of cochlear RNA from deaf mice lacking thyroid hormone receptor beta was used to identify a sequence encoding a secreted protein, which is abundant in the BM and is expressed at low levels in the heart, lung, and brain. The protein possesses several domains for protein interactions and is related to emilin (elastin microfibril interface-located protein) previously isolated from aorta. This cochlear emilin-2 mRNA is expressed in the tympanic border cells underlying the BM and an antibody detected protein in the extracellular matrix surrounding the collagenous fibers in the BM. These results identify emilin-2 as a major BM component and suggest that it contributes to the developmental assembly or function of the BM.
Amma
Lori L
LL
Department of Human Genetics, Box 1498, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY 10029, USA.
Goodyear
Richard
R
Faris
Jonathan S
JS
Jones
Iwan
I
Ng
Lily
L
Richardson
Guy
G
Forrest
Douglas
D
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary; D016326:Extracellular Matrix Proteins / Q000032:analysis / Q000235:genetics*; D015870:Gene Expression; D006023:Glycoproteins / Q000032:analysis / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009925:Organ of Corti / Q000737:chemistry / Q000502:physiology* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000032:analysis
D018076:DNA, Complementary; C486064:Emilin2 protein, mouse; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D012333:RNA, Messenger