title: Comparison of cell wall metabolism in the pulp of three cultivars of 'Nanfeng' tangerine differing in mastication trait.
abstract: BACKGROUND
  Like sweet orange (Citrus sinensis), tangerine (Citrus reticulata) is another citrus crop grown widely throughout the world. However, whether it shares a common mechanism with sweet orange in forming a given mastication trait is still unclear. In this study, three 'Nanfeng' tangerine cultivars, 'Yangxiao-26' ('YX-26') with inferior mastication trait, elite 'YX-26' with moderate mastication trait and 'Miguang' ('MG') with superior mastication trait, were selected to investigate the formation mechanism of mastication trait.
  
  
  RESULTS
  'MG' had the lowest contents of total pectin, protopectin and lignin and the highest gene expression levels of citrus polygalacturonase (PG) and pectin methylesterase (PME) at the end of fruit ripening, whereas 'YX-26' had the lowest water-soluble pectin (WSP) content, the highest lignin content and the lowest PG and PME expression levels. The contents of cellulose and hemicellulose were similar among the three tangerines.
  
  
  CONCLUSIONS
  The fruit mastication trait of C. reticulata was determined by the proportions of WSP and protopectin as well as lignin content, not by cellulose and hemicellulose contents. Pectin content could be a major contribution to the feeling of mastication trait, while PG and PME exhibited an important role in forming a given mastication trait according to the present results as well as previous results for C. sinensis.
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan 430070, China; State Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China.
authors: Ying
authors: Y
authors: Lei
authors: Yong-Zhong
authors: YZ
authors: Liu
authors: Qing-Qing
authors: QQ
authors: Gu
authors: Xiao-Yan
authors: XY
authors: Yang
authors: Xiu-Xin
authors: XX
authors: Deng
authors: Jin-Yin
authors: JY
authors: Chen
mesh_terms: D002265:Carboxylic Ester Hydrolases / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D002473:Cell Wall / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D002482:Cellulose / Q000032:analysis / Q000096:biosynthesis; D055598:Chemical Phenomena; D002681:China; D002957:Citrus / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D063427:Food Quality; D005638:Fruit / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006801:Humans; D008031:Lignin / Q000032:analysis / Q000096:biosynthesis*; D008409:Mastication; D010368:Pectins / Q000032:analysis / Q000096:biosynthesis* / Q000737:chemistry; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D011096:Polygalacturonase / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D011134:Polysaccharides / Q000032:analysis / Q000096:biosynthesis; D012677:Sensation; D012995:Solubility; D013045:Species Specificity
chemical_list: D010940:Plant Proteins; D011134:Polysaccharides; C586814:citrus pectin; C007916:hemicellulose; D010368:Pectins; D002482:Cellulose; D008031:Lignin; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase; D011096:Polygalacturonase