Selective expression of an endogenous lactose-binding lectin gene in subsets of central and peripheral neurons.
Cellular interactions in a variety of vertebrate non-neural tissues are thought to be mediated by cell surface carbohydrate structures. The detection of cell-specific surface carbohydrates and carbohydrate-binding proteins within the embryonic nervous system has raised the possibility that carbohydrate recognition may also contribute to the interactions of developing neurons. Soluble lactose-binding lectins constitute one class of carbohydrate-binding proteins expressed in the vertebrate nervous system. We describe here the isolation of cDNAs from rat brain libraries encoding one of these lectins, RL-14.5, and demonstrate that this protein is not only homologous to other soluble lectins, but also identical in primary sequence to a lectin present in at least one non-neural tissue. RNA blot analysis and in situ hybridization reveal a restricted pattern of expression of RL-14.5 mRNA within the rat nervous system. High levels of RL-14.5 mRNA are present in primary sensory neurons and motoneurons in the spinal cord and brain stem. Moreover, expression of RL-14.5 mRNA in sensory and motoneurons is detectable soon after neuronal differentiation. These findings, together with previous studies demonstrating the selective expression of oligosaccharide ligands for RL-14.5 on the same neurons, are consistent with the idea that carbohydrate-mediated interactions contribute to the development of this subset of mammalian neurons.
Hynes
M A
MA
Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, New York 10032.
Gitt
M
M
Barondes
S H
SH
Jessell
T M
TM
Buck
L B
LB
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002490:Central Nervous System / Q000166:cytology / Q000378:metabolism*; D004247:DNA / Q000302:isolation & purification; D037541:Galectin 4; D015870:Gene Expression; D006388:Hemagglutinins / Q000235:genetics*; D037102:Lectins / Q000235:genetics; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D009475:Neurons, Afferent / Q000378:metabolism; D010525:Peripheral Nerves / Q000166:cytology / Q000378:metabolism*; D014018:Tissue Distribution
D037541:Galectin 4; D006388:Hemagglutinins; D037102:Lectins; D004247:DNA