Effect of phenylalanine and alpha-methylphenylalanine on in vitro incorporation of 32P into cytoskeletal cerebral proteins.
We studied the effects of L-phenylalanine and alpha-methylphenylalanine on 32P in vitro incorporation into cytoskeletal proteins from cerebral cortex of 17-day-old rats. Slices of cerebral cortex were incubated in the absence or presence of increasing concentrations of L-phenylalanine, alpha-methylphenylalanine or L-phenylalanine plus alpha-methylphenylalanine for 1 h. The cytoskeletal fraction obtained from slices was incubated in the presence of the same drugs and the 32P in vitro incorporation into cytoskeletal proteins was measured. Addition of alpha-methylphenylalanine did not change 32P in vitro incorporation into the cytoskeletal proteins, but phenylalanine decreased the in vitro phosphorylation of beta tubulin. Furthermore, addition of L-phenylalanine plus alpha-methylphenylalanine decreased the in vitro phosphorylation of both 160 kDa neurofilaments and alpha-tubulin.
de Freitas
M S
MS
Departamento de Bioquimica, Instituto de Biociencias, UFRGS, Porto Alegre, RS Brasil.
de Mattos
A G
AG
Camargo
M M
MM
Wannmacher
C M
CM
Pessoa-Pureur
R
R
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D010761:Phosphorus Radioisotopes; D051381:Rats; D017208:Rats, Wistar
D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; D010761:Phosphorus Radioisotopes; C012436:alpha-methylphenylalanine; D010649:Phenylalanine