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Negative Feedbacks by Isoprenoids on a Mevalonate Kinase Expressed in the Corpora Allata of Mosquitoes.

Nyati P, Rivera-Perez C, Noriega FG - PLoS ONE (2015)

Bottom Line: AaMVK exhibited efficient inhibition by GPP and FPP (Ki less than 1 μM), and none by isopentenyl pyrophosphate (IPP) and dimethyl allyl pyrophosphate (DPPM).These results suggest that GPP and FPP might act as physiological inhibitors in the synthesis of isoprenoids in the CA of mosquitoes.Changing MVK activity can alter the flux of precursors and therefore regulate juvenile hormone biosynthesis.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Florida International University, Miami, FL, 33199, United States of America.

ABSTRACT

Background: Juvenile hormones (JH) regulate development and reproductive maturation in insects. JHs are synthesized through the mevalonate pathway (MVAP), an ancient metabolic pathway present in the three domains of life. Mevalonate kinase (MVK) is a key enzyme in the MVAP. MVK catalyzes the synthesis of phosphomevalonate (PM) by transferring the γ-phosphoryl group from ATP to the C5 hydroxyl oxygen of mevalonic acid (MA). Despite the importance of MVKs, these enzymes have been poorly characterized in insects.

Results: We functionally characterized an Aedes aegypti MVK (AaMVK) expressed in the corpora allata (CA) of the mosquito. AaMVK displayed its activity in the presence of metal cofactors. Different nucleotides were used by AaMVK as phosphoryl donors. In the presence of Mg(2+), the enzyme has higher affinity for MA than ATP. The activity of AaMVK was regulated by feedback inhibition from long-chain isoprenoids, such as geranyl diphosphate (GPP) and farnesyl diphosphate (FPP).

Conclusions: AaMVK exhibited efficient inhibition by GPP and FPP (Ki less than 1 μM), and none by isopentenyl pyrophosphate (IPP) and dimethyl allyl pyrophosphate (DPPM). These results suggest that GPP and FPP might act as physiological inhibitors in the synthesis of isoprenoids in the CA of mosquitoes. Changing MVK activity can alter the flux of precursors and therefore regulate juvenile hormone biosynthesis.

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Motifs derived from MVK amino acid sequence alignments display consensus sequences.Sequence logos for motif I, II and II were built using Weblogo [27]. The overall height of the stack indicates the sequence conservation at that position, colors denote the chemical properties of the amino acids. The sequences used are: Aedes aegypti (AAEL006435), Culex quinquefasciatus (EDS42994), Anopheles gambiae (EAA14782), Drosophila melanogaster (AGB93455), Bombyx mori (NP_001093299), Danaus plexippus (EHJ79258), Apis mellifera (XP_006558673), Acyrthosiphon pisum (XP_001942835) and Rattus norvegicus (NP_112325). Colors denote the chemical properties of the amino acids shown in each motif. Polar: G, S, T, Y, C; Neutral: Q; Basic: K, R, H; Acid: D, E; Hydrophobic: A, V, L, I, P, W, F, M.
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pone.0143107.g001: Motifs derived from MVK amino acid sequence alignments display consensus sequences.Sequence logos for motif I, II and II were built using Weblogo [27]. The overall height of the stack indicates the sequence conservation at that position, colors denote the chemical properties of the amino acids. The sequences used are: Aedes aegypti (AAEL006435), Culex quinquefasciatus (EDS42994), Anopheles gambiae (EAA14782), Drosophila melanogaster (AGB93455), Bombyx mori (NP_001093299), Danaus plexippus (EHJ79258), Apis mellifera (XP_006558673), Acyrthosiphon pisum (XP_001942835) and Rattus norvegicus (NP_112325). Colors denote the chemical properties of the amino acids shown in each motif. Polar: G, S, T, Y, C; Neutral: Q; Basic: K, R, H; Acid: D, E; Hydrophobic: A, V, L, I, P, W, F, M.

Mentions: The full-length AaMVK open reading frame is 1818 bp long (AAEL006435) [31, 32], and encodes a 397-aa protein with a calculated molecular mass of 43.27 kDa and a pI of 5.8. Amino acid sequence alignments of MVKs from insect and vertebrate species revealed 30–44% similarities (S1 Fig). The three conserved motifs that characterize MVKs were highly conserved among all the sequences analyzed, corroborating the functional role of AaMVK as a kinase (Fig 1). Motif I: containing part of the active site (PGKVILXGEHSVVXXXPA); motif II: a conserved glycine-rich motif (SIGXGLGSSAG) that forms a phosphate-binding loop in all GHMP kinases, and motif III: a conserved amino acid sequence (KLTGAGGGGC) that stabilizes the phosphate binding loop [5, 9].


Negative Feedbacks by Isoprenoids on a Mevalonate Kinase Expressed in the Corpora Allata of Mosquitoes.

Nyati P, Rivera-Perez C, Noriega FG - PLoS ONE (2015)

Motifs derived from MVK amino acid sequence alignments display consensus sequences.Sequence logos for motif I, II and II were built using Weblogo [27]. The overall height of the stack indicates the sequence conservation at that position, colors denote the chemical properties of the amino acids. The sequences used are: Aedes aegypti (AAEL006435), Culex quinquefasciatus (EDS42994), Anopheles gambiae (EAA14782), Drosophila melanogaster (AGB93455), Bombyx mori (NP_001093299), Danaus plexippus (EHJ79258), Apis mellifera (XP_006558673), Acyrthosiphon pisum (XP_001942835) and Rattus norvegicus (NP_112325). Colors denote the chemical properties of the amino acids shown in each motif. Polar: G, S, T, Y, C; Neutral: Q; Basic: K, R, H; Acid: D, E; Hydrophobic: A, V, L, I, P, W, F, M.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4643977&req=5

pone.0143107.g001: Motifs derived from MVK amino acid sequence alignments display consensus sequences.Sequence logos for motif I, II and II were built using Weblogo [27]. The overall height of the stack indicates the sequence conservation at that position, colors denote the chemical properties of the amino acids. The sequences used are: Aedes aegypti (AAEL006435), Culex quinquefasciatus (EDS42994), Anopheles gambiae (EAA14782), Drosophila melanogaster (AGB93455), Bombyx mori (NP_001093299), Danaus plexippus (EHJ79258), Apis mellifera (XP_006558673), Acyrthosiphon pisum (XP_001942835) and Rattus norvegicus (NP_112325). Colors denote the chemical properties of the amino acids shown in each motif. Polar: G, S, T, Y, C; Neutral: Q; Basic: K, R, H; Acid: D, E; Hydrophobic: A, V, L, I, P, W, F, M.
Mentions: The full-length AaMVK open reading frame is 1818 bp long (AAEL006435) [31, 32], and encodes a 397-aa protein with a calculated molecular mass of 43.27 kDa and a pI of 5.8. Amino acid sequence alignments of MVKs from insect and vertebrate species revealed 30–44% similarities (S1 Fig). The three conserved motifs that characterize MVKs were highly conserved among all the sequences analyzed, corroborating the functional role of AaMVK as a kinase (Fig 1). Motif I: containing part of the active site (PGKVILXGEHSVVXXXPA); motif II: a conserved glycine-rich motif (SIGXGLGSSAG) that forms a phosphate-binding loop in all GHMP kinases, and motif III: a conserved amino acid sequence (KLTGAGGGGC) that stabilizes the phosphate binding loop [5, 9].

Bottom Line: AaMVK exhibited efficient inhibition by GPP and FPP (Ki less than 1 μM), and none by isopentenyl pyrophosphate (IPP) and dimethyl allyl pyrophosphate (DPPM).These results suggest that GPP and FPP might act as physiological inhibitors in the synthesis of isoprenoids in the CA of mosquitoes.Changing MVK activity can alter the flux of precursors and therefore regulate juvenile hormone biosynthesis.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Florida International University, Miami, FL, 33199, United States of America.

ABSTRACT

Background: Juvenile hormones (JH) regulate development and reproductive maturation in insects. JHs are synthesized through the mevalonate pathway (MVAP), an ancient metabolic pathway present in the three domains of life. Mevalonate kinase (MVK) is a key enzyme in the MVAP. MVK catalyzes the synthesis of phosphomevalonate (PM) by transferring the γ-phosphoryl group from ATP to the C5 hydroxyl oxygen of mevalonic acid (MA). Despite the importance of MVKs, these enzymes have been poorly characterized in insects.

Results: We functionally characterized an Aedes aegypti MVK (AaMVK) expressed in the corpora allata (CA) of the mosquito. AaMVK displayed its activity in the presence of metal cofactors. Different nucleotides were used by AaMVK as phosphoryl donors. In the presence of Mg(2+), the enzyme has higher affinity for MA than ATP. The activity of AaMVK was regulated by feedback inhibition from long-chain isoprenoids, such as geranyl diphosphate (GPP) and farnesyl diphosphate (FPP).

Conclusions: AaMVK exhibited efficient inhibition by GPP and FPP (Ki less than 1 μM), and none by isopentenyl pyrophosphate (IPP) and dimethyl allyl pyrophosphate (DPPM). These results suggest that GPP and FPP might act as physiological inhibitors in the synthesis of isoprenoids in the CA of mosquitoes. Changing MVK activity can alter the flux of precursors and therefore regulate juvenile hormone biosynthesis.

Show MeSH