Calpain-PKC inter-relations in mouse hippocampus: a biochemical approach.
In previous studies, we isolated and identified a mu-calpain/PKCalpha complex from rabbit skeletal muscle. Here, we have used specific purification procedures in order to study the interactions between mu-calpain and PKC in mouse hippocampus, a brain structure implicated in memory processes. We observed that mu-calpain and conventional PKCs (alpha, betaII and gamma) are co-eluted after anion exchange chromatography. In contrast to our previous results obtained on skeletal muscle, mu-calpain and PKC isoenzymes were dissociated after gel filtration chromatography. Furthermore, mu-calpain induced the proteolytic conversion of PKCalpha, betaII, and gamma into PKMalpha, betaII, and gamma with a preferential hydrolysis of PKCgamma, a specific isoenzyme of the nervous system. Although the mu-calpain/PKC interactions in the hippocampus are quite different from skeletal muscle, our results however, point out the functional importance of these inter-relations. Moreover, as PKCgamma has been involved in the biochemical events underlying learning and memory, the preferential relationship between mu-calpain and PKCgamma promotes the importance of the role that mu-calpain could play in the cellular mechanisms of memory formation.
Touyarot
K
K
ISTAB, Laboratoire de Biochimie et Technologie des Aliments, Université Bordeaux I, UA-INRA 429, Talence, France.
Poussard
S
S
Verret
C
C
Aragon
B
B
Cottin
P
P
Nogues
X
X
Micheau
J
J
D000818:Animals; D002154:Calpain / Q000302:isolation & purification / Q000378:metabolism*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D006624:Hippocampus / Q000201:enzymology / Q000378:metabolism*; D006868:Hydrolysis; D051379:Mice; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology / Q000378:metabolism
D011493:Protein Kinase C; D002154:Calpain