Maize Carbohydrate Partitioning Defective33 Encodes an MCTP Protein and Functions in Sucrose Export from Leaves

作     者：Thu M.Tran Tyler J.McCubbin Saadia Bihmidine Benjamin T.Julius R.Frank Baker Martin Schauflinger Clifford Weil Nathan Springer Paul Chomet Ruth Wagner Jeff Woessner Karen Grote Jeanette Peevers Thomas L.Slewinski David M.Braun 

作者机构：Division of Biological Sciences’Interdisciplinary Plant GroupMissouri Maize CenterUniversity of MissouriColumbiaMO 65211USA Division of Plant SciencesUniversity of MissouriColumbiaMO 65211USA Electron Microscopy Core FacilityUniversity of MissouriColumbiaMO 65211USA Department of AgronomyPurdue UniversityWest LafayetteIN 47907USA Department of Plant and Microbial BiologyUniversity of MinnesotaSaint PaulMN 55108USA NRGene Inc.8910 University Center Lane\r\n S u ite 400San DiegoCA 92122USA Bayer Crop ScienceChesterfieldMO 63017USA National Key Laboratory for Plant Cell TechnologyAgricultural Genetics InstituteHanoiVietnam 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2019年第12卷第9期

页      面：1278-1293页

核心收录：

学科分类：0710[理学-生物学] 09[农学] 0901[农学-作物学] 0902[农学-园艺学] 

基　　金：supported by US National Science Foundation Plant Genome Research Program grant supported by University of Missouri Electron Microscopy Core's EM Excellence Award to T.M.T supported by the Vietnam International Education Development Fellowship 

主　　题：carbohydrate accumulation companion cells phloem, plasmodesmata sieve elements symplastictransport 

摘      要：To sustain plant growth,development,and crop yield,sucrose must be transported from leaves to distant parts of the plant,such as seeds and *** identify genes that regulate sucrose accumulation and transport in maize(Zea mays),we isolated carbo/iydrafe part/f/ofi/ngf defecf/Ve33(cpd33),a recessive mutant that accumulated excess starch and soluble sugars in mature *** cpd33 mutants also exhibited chlorosis in the leaf blades,greatly diminished plant growth,and reduced ***33 encodes a protein containing multiple C2 domains and transmembrane *** localization experiments showed the CPD33 protein localized to plasmodesmata(PD),the plasma membrane,and the endoplasmic *** also found that a loss-of-function mutant of the CPD33 homolog in Arabidopsis,QUIRKY,had a similar carbohydrate hyperaccumulation *** labeled sucrose transport assays showed that sucrose export was significantly lower in cpd33 mutant leaves relative to wild-type ***,PD transport in the adaxial-abaxial direction was unaffected in cpd33 mutant ***,transmission electron microscopy revealed fewer PD at the companion cell-sieve element interface in mutant phloem tissue,providing a possible explanation for the reduced sucrose export in mutant ***,our results suggest that CPD33 functions to promote symplastic transport into sieve elements.