TY - JOUR
T1 - Ethylene is required for both the initiation and progression of softening in pear (Pyrus communis L.) fruit
AU - Hiwasa, Kyoko
AU - Kinugasa, Yuichi
AU - Amano, Satomi
AU - Hashimoto, Akiko
AU - Nakano, Ryohei
AU - Inaba, Akitsugu
AU - Kubo, Yasutaka
N1 - Funding Information:
The authors would like to thank Dr JKC Rose (Cornell University, Ithaca, New York) for his helpful advice and critical reading of this manuscript. We also thank Dr JC Pech (ENSAT UMR INRA, France) and Mr WZO Owino (Okayama University, Japan) for their helpful advice. This work was supported in part by Grants-in-Aid for Scientific Research (grant no. 09660029 to YK and 11460013 to AI) and JSPS Research Fellowships for Young Scientists (grant no. 6509 to KH) from the Ministry of Education, Science, Sports and Culture of Japan. The sequences of PC-PG1, PC-PG2, PC-EG1, and PC-EG2 of pear (cv. La France) have been submitted to DDBJ under Accession numbers AB084461, AB084462, AB084463, and AB084464, respectively.
PY - 2003/2
Y1 - 2003/2
N2 - In order to investigate the physiological role of ethylene in the initiation and subsequent progression of softening, pear fruit were treated with propylene, an analogue of ethylene or 1-methylcyclopropene (1-MCP), a gaseous inhibitor of ethylene action at the preclimacteric or ripening stages. The propylene treatment at the pre-ripe stage stimulated ethylene production and flesh softening while the 1-MCP treatment at the same stage markedly retarded the initiation of the ripening-related events. Moreover, 1-MCP treatment after the initiation of ripening markedly suppressed the subsequent flesh softening and ethylene production. These results clearly indicate that ethylene is not merely a by-product, but plays a crucial role in both the initiation and maintenance of regulating the softening process during ripening. The observations also suggest that ethylene in ripening is regulated entirely in an autocatalytic manner. The mRNA accumulation of pear polygalacturonases (PG) genes, PC-PG1 and PC-PG2, was in parallel with the pattern of fruit softening in both propylene and 1-MCP treatments. However, the expression pattern of pear endo-1,4-β-D-glucanases (EGase) genes, PC-EG1 and PC-EG2, was not affected in both treatments. The results suggest that ethylene is required for PGs expression even in the late ripening stage, but not for EGases.
AB - In order to investigate the physiological role of ethylene in the initiation and subsequent progression of softening, pear fruit were treated with propylene, an analogue of ethylene or 1-methylcyclopropene (1-MCP), a gaseous inhibitor of ethylene action at the preclimacteric or ripening stages. The propylene treatment at the pre-ripe stage stimulated ethylene production and flesh softening while the 1-MCP treatment at the same stage markedly retarded the initiation of the ripening-related events. Moreover, 1-MCP treatment after the initiation of ripening markedly suppressed the subsequent flesh softening and ethylene production. These results clearly indicate that ethylene is not merely a by-product, but plays a crucial role in both the initiation and maintenance of regulating the softening process during ripening. The observations also suggest that ethylene in ripening is regulated entirely in an autocatalytic manner. The mRNA accumulation of pear polygalacturonases (PG) genes, PC-PG1 and PC-PG2, was in parallel with the pattern of fruit softening in both propylene and 1-MCP treatments. However, the expression pattern of pear endo-1,4-β-D-glucanases (EGase) genes, PC-EG1 and PC-EG2, was not affected in both treatments. The results suggest that ethylene is required for PGs expression even in the late ripening stage, but not for EGases.
KW - 1-methyl-cyclopropene
KW - Endo-1,4-β--glucanase
KW - Ethylene
KW - Pear fruit ripening
KW - Polygalacturonase
KW - Softening
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U2 - 10.1093/jxb/erg073
DO - 10.1093/jxb/erg073
M3 - Article
C2 - 12554720
AN - SCOPUS:0037322257
VL - 54
SP - 771
EP - 779
JO - Journal of Experimental Botany
JF - Journal of Experimental Botany
SN - 0022-0957
IS - 383
ER -