Title:	Disassembly of the fruit cell wall by the ripening-associated polygalacturonase and expansin in fluences tomato cracking.
Authors:	JIANG, F. LOPEZ, A. JEON, S. FREITAS, S. T. de YU, Q. WU, Z. LABAVITCH, J. M. TIAN, S. POWELL, A. L. T. MITCHAM, E.
Affiliation:	FANGLING JIANG; ALFONSO LOPEZ; SHINJAE JEON; SERGIO TONETTO DE FREITAS, CPATSA; QINGHUI YU; ZHEN WU; JOHN M. LABAVITCH; SHENGKE TIAN; ANN L. T. POWELL; ELIZABETH MITCHAM.
Date Issued:	2019
Citation:	Horticulture Research, v. 6, p. 1-15, 2019.
Description:	Fruit cracking is an important problem in horticultural crop production. Polygalacturonase (SlPG) and expansin (SlEXP1) proteins cooperatively disassemble the polysaccharide network of tomato fruit cell walls during ripening and thereby, enable softening. A Golden 2-like (GLK2) transcription factor, SlGLK2 regulates unripe fruit chloroplast development and results in elevated soluble solids and carotenoids in ripe fruit. To determine whether SlPG, SlEXP1, or SlGLK2 influence the rate of tomato fruit cracking, the incidence of fruit epidermal cracking was compared between wild-type, Ailsa Craig (WT) and fruit with suppressed SlPG and SlEXP1 expression (pg/exp) or expressing a truncated nonfunctional Slglk2 (glk2). Treating plants with exogenous ABA increases xylemic flow into fruit. Our results showed that ABA treatment of tomato plants greatly increased cracking of fruit from WT and glk2 mutant, but not from pg/exp genotypes. The pg/exp fruit were firmer, had higher total soluble solids, denser cell walls and thicker cuticles than fruit of the other genotypes. Fruit from the ABA treated pg/exp fruit had cell walls with less water-soluble and more ionically and covalently-bound pectins than fruit from the other lines, demonstrating that ripening-related disassembly of the fruit cell wall, but not elimination of SlGLK2, influences cracking. Cracking incidence was significantly correlated with cell wall and wax thickness, and the content of cell wall protopectin and cellulose, but not with Ca2+ content.
Thesagro:	Tomate Hortaliça Distúrbio Fisiológico
NAL Thesaurus:	Fruit cracking Horticultural crops
Keywords:	Proteínas poligalacturonase
DOI:	10.1038/s41438-018-0105-3
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CPATSA)