title: A comparative study of proteomic differences between pencil and storage roots of sweetpotato (Ipomoea batatas (L.) Lam.).
abstract: Fibrous roots of sweetpotato (Ipomoea batatas (L.) Lam.) usually develop into both pencil and storage roots. To understand protein function in root development, a proteomic analysis was conducted on the pencil and storage roots of the light orange-fleshed sweetpotato cultivar, Yulmi. Two-dimensional gel electrophoresis showed that expression of 30 protein spots differed between pencil and storage roots: 15 proteins were up-regulated or expressed in pencil roots and 15 in storage roots. Differentially expressed proteins spots were investigated using matrix-assisted laser desorption/ionization time of flight mass spectrometry, and 10 proteins from pencil roots were identified as binding protein isoform A, catechol oxidase, peroxidases, ascorbate peroxidase, endochitinase, flavanone 3-hydroxylase and unknown proteins. Of the proteins up-regulated in, or restricted to, storage roots, 13 proteins were identified as protein disulfide isomerase, anionic peroxidase, putative ripening protein, sporamin B, sporamin A and sporamin A precursor. An analysis of enzyme activity revealed that catechol oxidase and peroxidase as the first and last enzymes of the lignin biosynthesis pathway, and ascorbate peroxidase had higher activities in pencil than in storage roots. The total concentration of phenolic compounds was also far higher in pencil than in storage roots, and lignin accumulated only in pencil roots. These results provide important insight into sweetpotato proteomics, and imply that lignin biosynthesis and stress-related proteins are up-regulated or uniquely expressed in pencil roots. The results indicate that the reduction of carbon flow toward phenylpropanoid biosynthesis and its delivery to carbohydrate metabolism is a major event in storage root formation.
authors.affiliation: Department of Applied Biology, IALS, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Jeung Joo
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Biology Education, College of Education, IALS, PMBBRC, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Yun-Hee
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Applied Biology, IALS, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Youn-Sig
authors.initials: YS
authors.lastname: Kwak
authors.affiliation: Department of Applied Biology, IALS, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: An
authors.affiliation: Division of Applied Life Science (BK21 Program), IALS, College of Agriculture and Life Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Pil Joo
authors.initials: PJ
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), IALS, PMBBRC, College of Agriculture and Life Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Byung Hyun
authors.initials: BH
authors.lastname: Lee
authors.affiliation: Division of Applied Life Science (BK21 Program), PMBBRC, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Vikranth
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Department of Crop Science, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Kee Woong
authors.initials: KW
authors.lastname: Park
authors.affiliation: Gyeongsangnam-do Agricultural Research & Extension Services, Jinju 660-985, Republic of Korea.
authors.forename: Eun Sil
authors.initials: ES
authors.lastname: Chang
authors.affiliation: Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Republic of Korea.
authors.forename: Jae Cheol
authors.initials: JC
authors.lastname: Jeong
authors.affiliation: Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Republic of Korea.
authors.forename: Haeng-Soon
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Republic of Korea. Electronic address: sskwak@kribb.re.kr.
authors.forename: Sang-Soo
authors.initials: SS
authors.lastname: Kwak
mesh_terms: D027723:Ipomoea batatas / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D035281:Plant Tubers / Q000235:genetics / Q000378:metabolism*; D020543:Proteome / Q000096:biosynthesis* / Q000235:genetics; D040901:Proteomics
chemical_list: D010940:Plant Proteins; D020543:Proteome
keywords: Lignin biosynthesis; Pencil root; Proteomics; Storage root; Sweetpotato