Molecular interaction of neurocalcin alpha with alsin (ALS2).
Membrane microdomains (MDs), or lipid rafts, are recently identified dynamic membrane domains on which various signal-transductions are performed. Intracellular Ca(2+)-binding proteins participate in the Ca(2+) signaling through interaction with various proteins. Neurocalcin alpha (NCalpha) is a member of neuronal calcium sensor (NCS) protein family and shows Ca(2+)-dependent binding to the cell membrane through N-terminal myristoyl moiety. Since NCalpha was identified as a Ca(2+)-dependent binding protein to neuronal MDs, its binding proteins may participate in the signal-transduction on the MDs. In an immunoprecipitate using anti-NCalpha antibody, alsin (ALS2), a protein product of one of the responsive genes for amyotrophic lateral sclerosis, was detected through LC-MS/MS. Specific antibody to alsin was produced and immunoprecipitation using this antibody showed co-sedimentation of NCalpha. Some part of alsin bound to brain-derived MD fraction in the presence of Ca(2+) ions and eluted out by the chelation of Ca(2+) ions, as in the case of NCalpha. Immunostaining of cultured neurons showed broad distribution of alsin and NCalpha, and membrane association of these proteins were increased through Ca(2+) loading by maitotoxin. These results suggest that alsin binds cell membrane in a Ca(2+)-dependent manner through NCalpha and regulates membrane dynamics.
Masutani
Toshinori
T
Division of Biology, Graduate School of Science, Kobe-University, Rokkodaicho 1-1, Nada-ku, Kobe 657-8501, Japan.
Taguchi
Kastutoshi
K
Kumanogoh
Haruko
H
Nakamura
Shun
S
Maekawa
Shohei
S
D000818:Animals; D000831:Animals, Newborn; D001665:Binding Sites / Q000187:drug effects / Q000502:physiology; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000502:physiology*; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D006168:Guinea Pigs; D008387:Marine Toxins / Q000494:pharmacology; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism*; D019814:Myristic Acid / Q000378:metabolism; D051596:Neurocalcin / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D035964:Oxocins / Q000494:pharmacology; D011485:Protein Binding / Q000502:physiology*; D017434:Protein Structure, Tertiary / Q000502:physiology; D051381:Rats; D015398:Signal Transduction / Q000502:physiology; D013347:Subcellular Fractions; D000095702:Polyether Toxins
D002118:Calcium; D006152:Cyclic GMP; D020662:Guanine Nucleotide Exchange Factors; D008387:Marine Toxins; D019814:Myristic Acid; D051596:Neurocalcin; D035964:Oxocins; C512358:Als2 protein, mouse; C531118:Als2 protein, rat; C020394:maitotoxin; D000095702:Polyether Toxins