DNA Microarrays
SHOW DATA ...
link to BioGPS
Select Experiment :
Oocyte and Early Embryos
select experiment
OocyteDevelopment
PreEmbryoHuman
PreEmbryoMouse
PreimplantMmEmbryo
select experiment
Follicle_Maturation_and_Ovulation_POnly
Castrillon_Ovary_Set
Castrillon_Soma_Set
EmbryonicOvary
select experiment
Mm_Testis_Development
NormEndometrium
PituitaryAdenoma
Showing:
Preimplantation Mouse Embryo
Description :
Fields :
General Comment
Phospholipase A2 (EC 3.1.1.4 ) catalyzes the release of fatty acids from glycero-3-phosphocholines. The best known
varieties are the digestive enzymes secreted as zymogens by the pancreas of mammals. Sequences of pancreatic PLA2
enzymes from a variety of mammals have been reported. One striking feature of these enzymes is their close homology to
venom phospholipases of snakes.The phospholipases A2 (PLA2s), hydrolyze the sn-2 fatty acid acyl ester bond of phosphoglycerides,
releasing free fatty acids and lysophospholipids. The PLA2s constitute a diverse family of enzymes with
respect to sequence, function, localization, and divalent cation requirements. They play an important role in a
variety of cellular processes, including the digestion and metabolism of phospholipids as well as the
production of precursors for inflammatory reactions. The PLA2s have been classified into at least 5 groups
based on their size, structure, and need for divalent cations . Groups I, II, and III all contain
so-called secreted forms of PLA2, which are extracellular enzymes that have a low molecular mass and
require calcium ions for catalysis, while groups IV and V contain cytosolic forms of PLA2 that have a high
molecular mass and require calcium iron only in the case of group IV PLA2.
General function
Intracellular signaling cascade, Enzyme
Comment
Cellular localization
Secreted
Comment
Ovarian function
Ovulation, Luteolysis
Comment
Expression regulated by
FSH, LH, Steroids, Growth Factors/ cytokines
Comment
Kol S, et al 1997 reported that interleukin-1 beta stimulates ovarian phosphoipase A2 (PLA2)
expression and activity and up-regulation of both secretory and
cytosolic PLA2.
Interleukin (IL)-1 beta has been shown to stimulate ovarian prostaglandin
biosynthesis. The authors hypothesized that this effect entails the induction of phospholipase
A2 (PLA2). Treatment of cultured whole ovarian dispersates of immature rat origin
with IL-1 beta produced significant increases in 3H]arachidonic acid (AA) release
and [3H]prostanoid accumulation as well as increases in cellular PLA2 activity and
in secretory PLA2 and cytosolic PLA2 transcripts. Cotreatment with IL-1 receptor
antagonist reversed IL-mediated (and basal) release of [3H]labeled AA and
prostaglandin products, as well as cellular PLA2 activity. Treatment with IL-1 beta
also promoted a significant decrease in the cellular content of [3H]phospholipids
(apparently phosphatidylethanolamine but not phosphatidylcholine). These
observations establish the ovary as a site of IL-1-dependent sPLA2 and cPLA2 gene
expression, document the presence of a possible phosphatidylethanolamine-dependent
PLA2 activity in cultured whole ovarian dispersates, reveal the up-regulatory,
receptor-mediated action of IL-1 beta in this regard and suggest the existence of
endogenous PLA2-stimulating/ IL-1-like bioactivity.
[Kol S, et al 1997 reported studies on the rat ovarian phospholipase A2 system dealing with gene expression, cellular
localization, activity characterization, and interleukin-1 dependence.
Molecular probing of whole ovarian material revealed the immature rat
ovary to be a site of modest secretory PLA2 (sPLA2) gene expression. However, no
change in ovarian sPLA2 gene expression was noted during the periovulatory period.
Comparable probing for cytosolic PLA2 (cPLA2) failed to disclose a quantifiable
signal. However, in situ hybridization localized both sPLA2 and cPLA2 (sPLA2 >
cPLA2) transcripts to the granulosa cell layer of the ovarian follicle. Treatment of
cultured whole ovarian dispersates with IL-1 beta produced significant (P < 0.01)
increments in the steady state levels of transcripts corresponding to both sPLA2
(1.7-fold increase) and cPLA2 (5-fold increase), an effect reversed by an IL-1
receptor antagonist, suggesting mediation via a specific IL-1 receptor. Treatment with aminoguanidine, an inhibitor of inducible
nitric oxide synthase, led to augmentation of the ability of IL-1 beta to up-regulate
sPLA2 and cPLA2 gene expression as well as medium PLA2 activity. Total cellular
PLA2 activity proved time, cell density, and calcium dependent, with an optimal pH
of 8.0-9.0 and K(m) values in the low micromolar range (2-5 microM). The
observations 1) establish the rat ovary as a site of sPLA2 and cPLA2 gene expression,
2) localize the corresponding transcripts to the granulosa cell layer, and 3) establish
IL-1 beta as an up-regulatory agent for ovarian sPLA2 and cPLA2 gene expression as
well as for ovarian PLA2 activity. These findings also indicate that the IL-1 effect is
1) receptor mediated, 2) contingent in part upon de novo protein biosynthesis, and 3)
inhibited by nitric oxide. These observations support the proposition that PLA2 may
be a key component in the IL-1-stimulated biosynthesis of ovarian PGs.
Kol S, et al reported that glucocorticoids suppress basal (but not interleukin-1-supported)
ovarian phospholipase A2 activity and evidence for glucocorticoid
receptor-mediated regulation.
Ovarian localization
Granulosa, Luteal cells
Comment
Follicle stages
Comment
Phenotypes
Mutations
0 mutations
Genomic Region
show genomic region
Phenotypes and GWAS
show phenotypes and GWAS
Links