AMP‐activated protein kinase ‐ An archetypal protein kinase cascade?

Hardie, D. Grahame; MacKintosh, Robert W.

doi:10.1002/bies.950141011

Cited by 46 publications

(34 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The activation can be partly explained by photosynthesis-dependent changes in pH, Mg2+, and adenine nucleotide levels in the chloroplast stroma (Harwood, 1988), but the other factors may be involved as well. In animals and yeasts, ACCase is a key enzyme in carbon metabolism and is regulated by AMP-activated protein kinase (Hardie and MacKintosh, 1992). We do not yet have evidence that the eukaryotic form of ACCase in plants is regulated in this manner.…”

Section: Roles Of the Two Forms Of Accasementioning

confidence: 92%

The Compartmentation of Acetyl-Coenzyme A Carboxylase in Plants

Sasaki¹,

Konishi²,

Nagano³

1995

Plant Physiol.

180

119

View full text Add to dashboard Cite

Although the biochemical pathways for fatty acid synthesis are more or less similar in plants and animals (Harwood, 1988), there is a major cell biological difference between these two groups of eukaryotes. In plants, the major site of fatty acid synthesis is the plastid, an organelle absent from the animal cell. Many aspects of plastid biology, including fatty acid synthesis, reflect the organelle's origins as a prokaryotic symbiont. The synthesis of fatty acids, such as palmitic acid, the prototype 16-carbon fatty acid, requires one molecule of acetyl-COA and seven molecules of malonyl-COA, which are added sequentially with the addition of two carbons to the growing fatty acid chain and the release of CO, at each step. These reactions are catalyzed by fatty acid synthase, an enzyme complex known to exist in a prokaryotic and a eukaryotic form (Wakil et al., 1983;Harwood, 1988). The prokaryotic form (type 11) of fatty acid synthase is found in plants. The synthase is composed of severa1 dissociable proteins, whereas the eukaryotic form (type I) found in animals and yeasts is composed of one or two large multifunctional, nondissociable proteins. For either form, the synthesis requires malonyl-COA, which is supplied by ACCase in the following reaction:In plant cells, large amounts of malonyl-COA are needed in the plastids to sustain fatty acid synthesis, but malonyl-COA is also needed in the cytosol for the elongation of fatty acids exported from the plastids and for the synthesis of flavonoids and phytoalexins. As with fatty acid synthase, ACCase also occurs in prokaryotic and eukaryotic forms in nature. The prokaryotic form is composed of dissociable polypeptides, whereas the eukaryotic form is a homodimer of a multifunctional protein. But which form(s) of this enzyme occur(s) in plants? Both or only one? This biochemical mystery, which has been around since 1972, has finally been solved and the answer is intriguing, both from a ' Present address:

show abstract

Section: Roles Of the Two Forms Of Accasementioning

confidence: 92%

The Compartmentation of Acetyl-Coenzyme A Carboxylase in Plants

Sasaki¹,

Konishi²,

Nagano³

1995

Plant Physiol.

180

119

View full text Add to dashboard Cite

show abstract

“…Conditions which induce cellular stress cause a large increase in intracellular AMP as well as a depletion of ATP and these changes correlate with activation of the 5'-AMP-activated protein kinase, The physiological targets of this enzyme are, besides HSL, acetyl-CoA carboxylase (EC 6.4.1.2) and 3-hydroxy-3-methylglutaryl-CoA reductase (EC 1.1.1.34) which catalyse regulated steps in the biosynthesis of fatty acids and isoprenoids andor steroids respectively. Therefore, in conditions of cellular stress, 5'-AMP-activated protein kinase has a possible protective role through inactivation of key enzymes involved in the synthesis or release of fatty acids and cholesterol (Hardie & McIntosh, 1992). Another possible regulation of HSL by 5'-AMP-activated protein kinase involves fatty acids.…”

Section: L a N G I N And O T H E R Smentioning

confidence: 99%

Adipocyte hormone-sensitive lipase: a major regulator of lipid metabolism

1996

View full text Add to dashboard Cite

Lipase hormono-sensible de l'adipocyte: un rCgulateur important du mCtabolisme lipidique R E S U M GLe tissu adipeux joue un r81e important dans le contrde de la balance CnergCtique. La mobilisation des triacylglycCrols par la lipase hormono-sensible (EC 3.1.1.3; LHS) est soumis a un contrBle direct par les hormones et neurotransmetteurs qui modulent les concentrations intracellulaires d'AMP cyclique (AMPc). L'hydrolyse des triacylglycCrols par la LHS constitue l'etape limitante de la lipolyse. La LHS est phosphorylCe sur le site rkgulateur (Ser552 dans la LHS humaine) par la p r o t h e kinase dependante de 1'AMPc (EC 2.7.1.37) lorsque les concentrations intracellulaires d' AMPc augmentent. Cette phosphorylation conduit B l'activation de l'enzyme. Une deuxikme site de phosphorylation (Ser5.54 dans la LHS humaine) dCnommC site basal est la cible de la protCine kinase activCe par I'AMP. La phosphorylation du site basal ne conduit pas B l'activation de la LHS et empkche la phosphorylation sur le site regulateur. La phosphorylation et I'activation de la protCine kinase activke par 1'AMP constitue donc un mecanisme antilipolytique qui est fonctionnel sur cellules isolCes mais dont l'importance physiologique n'est pas connue. Les ADN complkmentaires de la LHS de plusieurs espkces ont Ct C clones et la structure des gbnes de LHS de l'homme et de la souris sont connus. Differents domaines fonctionnels de la protCine ont Ct C proposes. Une rCgion d'homologie de sequences en amont de la serine 424 du site catalytique avec cinq enzymes d'organismes procaryotes et une enzyme humaine a ete decrite. La localisation chromosomique du gbne de la LHS est connue chez l'homme (chromosome 19, region q13-1+13.2), le porc et la souris. La mise en evidence de marqueurs polymorphiques dans le g&ne devrait permettre de tester l'hypothkse d'une implication de la LHS dans certaines maladies hereditaires du metabolisme lipidique. L'expression de la LHS varie selon la localisation anatomique du tissu adipeux chez le rat. Cette expression subit Cgalement des variations durant la gestation chez le rat et le cycle annuel chez les mammifbres hibernants. Chez l'homme, les taux d'ARN messagers de la LHS sont diminuCs dans le tissu adipeux de certains patients atteints de cancer. L'activitC enzymatique totale est diminuee chez les patients atteints d'hyperlipidemie familiale combinCe mais pas chez les patients atteints du syndrome metabolique bien que, dans les deux cas, la lipolyse adipocytaire maximale soit diminuke. Les mkcanismes molCculaires de contr6le de l'expression de la LHS sont pratiquement inconnus.

show abstract

“…In response to conditions ~¢hich elevate the AMP:ATP ratio, AMPK phosphorylates ~everal targets, especially biosynthetic enzymes such as HMGCoA reductase which are inactivated [3], thus providing a mechanism for conserving ATE We have recently discovered activities in higher plants which, by a number of biochemical criteria, appear to be homologues of AMPK. Since they appear aot to be directly activated by AMP, we have provisionally named them HMG-CoA reductase kinases (HRK-A and -B) i4,5].…”

Section: Introductionmentioning

confidence: 99%

Similar substrate recognition motifs for mammalian AMP‐activated protein kinase, higher plant HMG‐CoA reductase kinase‐A, yeast SNF1, and mammalian calmodulin‐dependent protein kinase I

et al. 1995

View full text Add to dashboard Cite

We have analysed phosphorylation of the synthetic peptide AMARAASAAALARRR, and 23 variants, by mammalian, higher plant and yeast members of the SNFI protein kinase subfamily (AMP-activated protein kinase (AMPK), HMG-CoA reductase kinase (HRK-A), and SNF1 itself), and by mammalian caimodulin-dependent protein kinase I (CaMKI). These four kinases recognize motifs which are very similar, although distinguishable. Our studies define the following recognition motifs: ~MPK: qr~K

show abstract

AMP‐activated protein kinase ‐ An archetypal protein kinase cascade?

Cited by 46 publications

References 44 publications

The Compartmentation of Acetyl-Coenzyme A Carboxylase in Plants

The Compartmentation of Acetyl-Coenzyme A Carboxylase in Plants

Adipocyte hormone-sensitive lipase: a major regulator of lipid metabolism

Similar substrate recognition motifs for mammalian AMP‐activated protein kinase, higher plant HMG‐CoA reductase kinase‐A, yeast SNF1, and mammalian calmodulin‐dependent protein kinase I

Contact Info

Product

Resources

About