LMBR1

This gene encodes a member of the LMBR1-like membrane protein family. Another member of this protein family has been shown to be a lipocalin transmembrane receptor. A highly conserved, cis-acting regulatory module for the sonic hedgehog gene is located within an intron of this gene. Consequently, disruption of this genic region can alter sonic hedgehog expression and affect limb patterning, but it is not known if this gene functions directly in limb development. Mutations and chromosomal deletions and rearrangements in this genic region are associated with acheiropody and preaxial polydactyly, which likely result from altered sonic hedgehog expression. [provided by RefSeq]

Full Name

limb region 1 homolog (mouse)

Function

Putative membrane receptor.

Biological Process

Embryonic digit morphogenesisIEA:Ensembl
Signal transductionManual Assertion Based On ExperimentIBA:GO_Central

Cellular Location

Membrane

Involvement in disease

Preaxial polydactyly 2 (PPD2):
Polydactyly consists of duplication of the distal phalanx. The thumb in PPD2 is usually opposable and possesses a normal metacarpal.
Acheiropody (ACHP):
Very rare condition characterized by bilateral congenital amputations of the hands and feet. The specific malformative phenotype consists of a complete amputation of the distal epiphysis of the humerus, amputation of the tibial diaphysis and aplasia of the radius, ulna, fibula and of all the bones of the hands and feet.
Syndactyly 4 (SDTY4):
A form of syndactyly, a congenital anomaly of the hand or foot marked by persistence of the webbing between adjacent digits that are more or less completely attached. SDTY4 is characterized by complete bilateral syndactyly (involving all digits 1 to 5). A frequent association with polydactyly (with six metacarpals and six digits) has been reported. Feet are affected occasionally.
Hypoplasia or aplasia of tibia with polydactyly (THYP):
An autosomal dominant disease characterized by hypoplastic or absent tibia, and polydactyly.
Laurin-Sandrow syndrome (LSS):
A rare autosomal dominant disorder characterized by polysyndactyly of hands and/or feet, mirror image duplication of the feet, nasal defects, and loss of identity between fibula and tibia. Some patients do not have nasal abnormalities (segmental Laurin-Sandrow syndrome).

Topology

Extracellular: 1-19
Helical: 20-40
Cytoplasmic: 41-62
Helical: 63-83
Extracellular: 84-110
Helical: 111-131
Cytoplasmic: 132-151
Helical: 152-172
Extracellular: 173-187
Helical: 188-208
Cytoplasmic: 209-291
Helical: 292-312
Extracellular: 313-339
Helical: 340-360
Cytoplasmic: 361-383
Helical: 384-404
Extracellular: 405-426
Helical: 427-447
Cytoplasmic: 448-490