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Biosynthesis and possible functions of inositol pyrophosphates in plants.

Williams SP, Gillaspy GE, Perera IY - Front Plant Sci (2015)

Bottom Line: Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid).Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom.This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.

View Article: PubMed Central - PubMed

Affiliation: Biochemistry, Virginia Polytechnic and State University Blacksburg, VA, USA.

ABSTRACT
Inositol phosphates (InsPs) are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5) bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e., PPx) attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration of cellular metabolism and stress signaling in non-plant eukaryotes. Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid). Even though plants produce huge amounts of precursor InsP6 in seeds, almost no attention has been paid to whether PPx-InsPs exist in plants, and if so, what roles these molecules play. Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom. This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.

No MeSH data available.


Related in: MedlinePlus

Structures of PPx-InsPs and pathway of proposed synthesis. The unboxed area is the last step in InsP6 synthesis, catalyzed by the IPK1 enzyme in plants. The boxed areas in blue and orange indicate InsP7 and InsP8 synthesis. The colored arrows indicate known enzymes in yeast. Red arrows indicate KCS1 activity, while yellow arrows indicate VIP activity. The green arrows indicate phosphatase activity by DDP1.
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Figure 2: Structures of PPx-InsPs and pathway of proposed synthesis. The unboxed area is the last step in InsP6 synthesis, catalyzed by the IPK1 enzyme in plants. The boxed areas in blue and orange indicate InsP7 and InsP8 synthesis. The colored arrows indicate known enzymes in yeast. Red arrows indicate KCS1 activity, while yellow arrows indicate VIP activity. The green arrows indicate phosphatase activity by DDP1.

Mentions: PPx-InsPs were first identified in Dictyostelium in 1993 (Glennon and Shears, 1993; Hawkins et al., 1993; Menniti et al., 1993; Stephens et al., 1993). They are similar to ATP and polyphosphates in that they contain a linear chain of two (PP) or three (PPP) phosphates separated by pyrophosphate bonds, linked to an InsP molecule (see Figure 2).


Biosynthesis and possible functions of inositol pyrophosphates in plants.

Williams SP, Gillaspy GE, Perera IY - Front Plant Sci (2015)

Structures of PPx-InsPs and pathway of proposed synthesis. The unboxed area is the last step in InsP6 synthesis, catalyzed by the IPK1 enzyme in plants. The boxed areas in blue and orange indicate InsP7 and InsP8 synthesis. The colored arrows indicate known enzymes in yeast. Red arrows indicate KCS1 activity, while yellow arrows indicate VIP activity. The green arrows indicate phosphatase activity by DDP1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4325660&req=5

Figure 2: Structures of PPx-InsPs and pathway of proposed synthesis. The unboxed area is the last step in InsP6 synthesis, catalyzed by the IPK1 enzyme in plants. The boxed areas in blue and orange indicate InsP7 and InsP8 synthesis. The colored arrows indicate known enzymes in yeast. Red arrows indicate KCS1 activity, while yellow arrows indicate VIP activity. The green arrows indicate phosphatase activity by DDP1.
Mentions: PPx-InsPs were first identified in Dictyostelium in 1993 (Glennon and Shears, 1993; Hawkins et al., 1993; Menniti et al., 1993; Stephens et al., 1993). They are similar to ATP and polyphosphates in that they contain a linear chain of two (PP) or three (PPP) phosphates separated by pyrophosphate bonds, linked to an InsP molecule (see Figure 2).

Bottom Line: Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid).Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom.This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.

View Article: PubMed Central - PubMed

Affiliation: Biochemistry, Virginia Polytechnic and State University Blacksburg, VA, USA.

ABSTRACT
Inositol phosphates (InsPs) are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5) bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e., PPx) attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration of cellular metabolism and stress signaling in non-plant eukaryotes. Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6)-hexakisphosphate (InsP6), which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid). Even though plants produce huge amounts of precursor InsP6 in seeds, almost no attention has been paid to whether PPx-InsPs exist in plants, and if so, what roles these molecules play. Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom. This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.

No MeSH data available.


Related in: MedlinePlus