Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism

Citric acid serves as the principal organic acid in citrus fruits, with its concentration critically determining fruit flavor and market acceptability. Isocitrate dehydrogenase (IDH), a key enzyme in citric acid metabolism, mediates the conversion of citrate to α-ketoglutarate. This study cloned six...

Full description

Saved in:
Bibliographic Details
Main Authors: Longfei Jin, Yang Yue, Feng Liu, Mingxia Wen, Bei Huang, Peng Wang
Format: Article
Language:English
Published: MDPI AG 2025-05-01
Series:Horticulturae
Subjects:
Online Access:https://www.mdpi.com/2311-7524/11/6/598
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850168521244278784
author Longfei Jin
Yang Yue
Feng Liu
Mingxia Wen
Bei Huang
Peng Wang
author_facet Longfei Jin
Yang Yue
Feng Liu
Mingxia Wen
Bei Huang
Peng Wang
author_sort Longfei Jin
collection DOAJ
description Citric acid serves as the principal organic acid in citrus fruits, with its concentration critically determining fruit flavor and market acceptability. Isocitrate dehydrogenase (IDH), a key enzyme in citric acid metabolism, mediates the conversion of citrate to α-ketoglutarate. This study cloned six candidate genes encoding IDH from grapefruit (<i>Citrus paradisi</i>). Bioinformatics analysis showed that all six genes contained the typical characteristic structure of IDH. Gene expression analysis found that <i>CpNADP-IDH1</i> is highly expressed in mature and low-acid varieties. Overexpression of <i>CpNADP-IDH1</i> significantly increased IDH enzyme activity and decreased citric acid content in transgenic grapefruit callus. These results showed that at least six genes encoding IDH exist in grapefruit, among which <i>CpNADP-IDH1</i> catalyzes the decomposition of citric acid and regulates the organic acid content in fruits at maturity. <i>CpNADP-IDH1</i> can be used as a candidate gene for molecular breeding of low-acid citrus varieties and as an essential target gene for developing citrus cultivation technology for reducing acid content.
format Article
id doaj-art-060e480876bd4cb08eae3a90b2ff80fb
institution OA Journals
issn 2311-7524
language English
publishDate 2025-05-01
publisher MDPI AG
record_format Article
series Horticulturae
spelling doaj-art-060e480876bd4cb08eae3a90b2ff80fb2025-08-20T02:20:57ZengMDPI AGHorticulturae2311-75242025-05-0111659810.3390/horticulturae11060598Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid MetabolismLongfei Jin0Yang Yue1Feng Liu2Mingxia Wen3Bei Huang4Peng Wang5Institute of Citrus Research, Zhejiang Academy of Agricultural Sciences, Taizhou 318026, ChinaCollege of Horticulture and Gardening, Yangtze University, Jingzhou 434025, ChinaInstitute of Citrus Research, Zhejiang Academy of Agricultural Sciences, Taizhou 318026, ChinaInstitute of Citrus Research, Zhejiang Academy of Agricultural Sciences, Taizhou 318026, ChinaInstitute of Citrus Research, Zhejiang Academy of Agricultural Sciences, Taizhou 318026, ChinaInstitute of Citrus Research, Zhejiang Academy of Agricultural Sciences, Taizhou 318026, ChinaCitric acid serves as the principal organic acid in citrus fruits, with its concentration critically determining fruit flavor and market acceptability. Isocitrate dehydrogenase (IDH), a key enzyme in citric acid metabolism, mediates the conversion of citrate to α-ketoglutarate. This study cloned six candidate genes encoding IDH from grapefruit (<i>Citrus paradisi</i>). Bioinformatics analysis showed that all six genes contained the typical characteristic structure of IDH. Gene expression analysis found that <i>CpNADP-IDH1</i> is highly expressed in mature and low-acid varieties. Overexpression of <i>CpNADP-IDH1</i> significantly increased IDH enzyme activity and decreased citric acid content in transgenic grapefruit callus. These results showed that at least six genes encoding IDH exist in grapefruit, among which <i>CpNADP-IDH1</i> catalyzes the decomposition of citric acid and regulates the organic acid content in fruits at maturity. <i>CpNADP-IDH1</i> can be used as a candidate gene for molecular breeding of low-acid citrus varieties and as an essential target gene for developing citrus cultivation technology for reducing acid content.https://www.mdpi.com/2311-7524/11/6/598citrusisocitrate dehydrogenasecitric acid<i>CpNADP-IDH1</i>
spellingShingle Longfei Jin
Yang Yue
Feng Liu
Mingxia Wen
Bei Huang
Peng Wang
Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
Horticulturae
citrus
isocitrate dehydrogenase
citric acid
<i>CpNADP-IDH1</i>
title Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
title_full Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
title_fullStr Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
title_full_unstemmed Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
title_short Identification of the Grapefruit (<i>Citrus paradisi</i>) Isocitrate Dehydrogenase Gene and Functional Analysis of <i>CpNADP-IDH1</i> in Citric Acid Metabolism
title_sort identification of the grapefruit i citrus paradisi i isocitrate dehydrogenase gene and functional analysis of i cpnadp idh1 i in citric acid metabolism
topic citrus
isocitrate dehydrogenase
citric acid
<i>CpNADP-IDH1</i>
url https://www.mdpi.com/2311-7524/11/6/598
work_keys_str_mv AT longfeijin identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism
AT yangyue identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism
AT fengliu identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism
AT mingxiawen identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism
AT beihuang identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism
AT pengwang identificationofthegrapefruiticitrusparadisiiisocitratedehydrogenasegeneandfunctionalanalysisoficpnadpidh1iincitricacidmetabolism