TY - JOUR
T1 - Neuronal expression and neuritogenic action of group X secreted phospholipase A2
AU - Masuda, Seiko
AU - Murakami, Makoto
AU - Takanezawa, Yasukazu
AU - Aoki, Junken
AU - Arai, Hiroyuki
AU - Ishikawa, Yukio
AU - Ishii, Toshiharu
AU - Arioka, Manabu
AU - Kudo, Ichiro
PY - 2005/6/17
Y1 - 2005/6/17
N2 - Although individual mammalian secreted phospholipase A2 (sPLA2) enzymes exhibit unique tissue and cellular distributions, the cell type-specific functions of each enzyme remain largely unknown. In this study, we found by immunohistochemistry that group X sPLA2 (sPLA 2-X) is uniquely located in the peripheral neuronal fibers, an observation that was supported by detection of its transcript and protein in the neuronal cell line PC12 and in primary dorsal root ganglia neurons. Adenoviral expression of sPLA2-X in PC12 cells facilitated neurite outgrowth, particularly when combined with a suboptimal concentration of nerve growth factor. In neuronally differentiated PC12 cells, sPLA2-X was preferentially localized in the Golgi apparatus and growth cones, and proteolytic conversion of the proenzyme to mature enzyme mainly occurred after the secretion process. The neurite-extending ability of sPLA2-X depended on the production of its catalytic product, lysophosphatidylcholine. Moreover, nerve growth factor-induced neurite extension of PC12 cells was modestly but significantly attenuated by an anti-sPLA2-X antibody or by a small interfering RNA for sPLA2-X. These observations suggest the potential contribution of sPLA2-X to neuronal differentiation, and possibly repair, under certain conditions.
AB - Although individual mammalian secreted phospholipase A2 (sPLA2) enzymes exhibit unique tissue and cellular distributions, the cell type-specific functions of each enzyme remain largely unknown. In this study, we found by immunohistochemistry that group X sPLA2 (sPLA 2-X) is uniquely located in the peripheral neuronal fibers, an observation that was supported by detection of its transcript and protein in the neuronal cell line PC12 and in primary dorsal root ganglia neurons. Adenoviral expression of sPLA2-X in PC12 cells facilitated neurite outgrowth, particularly when combined with a suboptimal concentration of nerve growth factor. In neuronally differentiated PC12 cells, sPLA2-X was preferentially localized in the Golgi apparatus and growth cones, and proteolytic conversion of the proenzyme to mature enzyme mainly occurred after the secretion process. The neurite-extending ability of sPLA2-X depended on the production of its catalytic product, lysophosphatidylcholine. Moreover, nerve growth factor-induced neurite extension of PC12 cells was modestly but significantly attenuated by an anti-sPLA2-X antibody or by a small interfering RNA for sPLA2-X. These observations suggest the potential contribution of sPLA2-X to neuronal differentiation, and possibly repair, under certain conditions.
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U2 - 10.1074/jbc.M500985200
DO - 10.1074/jbc.M500985200
M3 - Article
C2 - 15781456
AN - SCOPUS:20744443792
VL - 280
SP - 23203
EP - 23214
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 24
ER -