The presence of the 50-kDa subunit of dynactin complex in the nerve growth cone.
Membrane proteins in growth cone-enriched and growth cone-non-enriched fractions prepared from neonatal mouse brain were separated by lectin-affinity and ion exchange chromatographies, 2D-PAGE, and SDS-PAGE. Partial amino acid sequences of the proteins concentrated in the growth cone-enriched fraction were determined. We found that one such protein, gmp23-48k, corresponds to the 50-kDa subunit (p50) of the dynactin complex. An antibody raised against gmp23-48k strongly reacted with growth cones of differentiated neuronal precursor cells. Immunoblot analyses revealed that gmp23-48k was present both in membrane and in soluble fractions of neonatal brain. However, the amount of gmp23-48k in the membrane fraction greatly decreased in adult brain. These results suggest a special role of membrane-associated gmp23-48k/p50 in synapse formation during brain development.
Abe
T K
TK
Research Laboratory for Molecular Genetics, Niigata University, Asahimachi, Japan.
Tanaka
H
H
Iwanaga
T
T
Odani
S
S
Kuwano
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001369:Axons / Q000737:chemistry*; D002846:Chromatography, Affinity; D002852:Chromatography, Ion Exchange; D000072159:Dynactin Complex; D004398:Dyneins / Q000032:analysis*; D015180:Electrophoresis, Gel, Two-Dimensional; D007150:Immunohistochemistry; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000032:analysis*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011487:Protein Conformation; D016415:Sequence Alignment
D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; D004398:Dyneins