Abstract
The relationship between polygalacturonase activity and abscission of citrus leaf explants was studied. Determination of polygalacturonase activity in citrus tissues requires concentration of the enzyme, use of a proper assay method, and inhibition of an oxidase present in the extracts which oxidizes the reaction products of the polygalacturonase. The polygalacturonase from citrus leaf explants is an exopolygalacturonase and appears to be a soluble enzyme.
Polygalacturonase activity increased during abscission of citrus leaf explants and was localized in the separation layer. Ethylene accelerated the increase in polygalacturonase activity, but its effect was evident only after at least an 8-hour lag period. 2,4-Dichlorophenoxyacetic acid and cycloheximide inhibited abscission and polygalacturonase activity. It is concluded that polygalacturonase, in addition to cellulase, plays a role in abscission.
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- Abeles F. B. Abscission: role of cellulase. Plant Physiol. 1969 Mar;44(3):447–452. doi: 10.1104/pp.44.3.447. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Abeles F. B., Holm R. E., Gahagan H. E. Abscission: the role of aging. Plant Physiol. 1967 Oct;42(10):1351–1356. doi: 10.1104/pp.42.10.1351. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Abeles F. B. Role of RNA and protein synthesis in abscission. Plant Physiol. 1968 Sep;43(9 Pt B):1577–1586. [PMC free article] [PubMed] [Google Scholar]
- Dela Fuente R. K., Leopold A. C. Senescence processes in leaf abscission. Plant Physiol. 1968 Sep;43(9 Pt B):1496–1502. [PMC free article] [PubMed] [Google Scholar]
- Massey V., Müller F., Feldberg R., Schuman M., Sullivan P. A., Howell L. G., Mayhew S. G., Matthews R. G., Foust G. P. The reactivity of flavoproteins with sulfite. Possible relevance to the problem of oxygen reactivity. J Biol Chem. 1969 Aug 10;244(15):3999–4006. [PubMed] [Google Scholar]
- Moline H. E., Lamotte C. E., Gochnauer C., McNamer A. Further comparative studies of pectin esterase in relation to leaf and flower abscission. Plant Physiol. 1972 Dec;50(6):655–659. doi: 10.1104/pp.50.6.655. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morre D. J. Cell wall dissolution and enzyme secretion during leaf abscission. Plant Physiol. 1968 Sep;43(9 Pt B):1545–1559. [PMC free article] [PubMed] [Google Scholar]
- Rasmussen G. K. Changes in cellulase and pectinase activities in fruit tissues and separation zones of citrus treated with cycloheximide. Plant Physiol. 1973 Apr;51(4):626–628. doi: 10.1104/pp.51.4.626. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ratner A., Goren R., Monselise S. P. Activity of pectin esterase and cellulase in the abscission zone of citrus leaf explants. Plant Physiol. 1969 Dec;44(12):1717–1723. doi: 10.1104/pp.44.12.1717. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Riov J., Monselise S. P., Kahan R. S. Ethylene-controlled Induction of Phenylalanine Ammonia-lyase in Citrus Fruit Peel. Plant Physiol. 1969 May;44(5):631–635. doi: 10.1104/pp.44.5.631. [DOI] [PMC free article] [PubMed] [Google Scholar]
- TREVELYAN W. E., PROCTER D. P., HARRISON J. S. Detection of sugars on paper chromatograms. Nature. 1950 Sep 9;166(4219):444–445. doi: 10.1038/166444b0. [DOI] [PubMed] [Google Scholar]
- Webster B. D. Anatomical aspects of abscission. Plant Physiol. 1968 Sep;43(9 Pt B):1512–1544. [PMC free article] [PubMed] [Google Scholar]
- Yager R. E. Possible Role of Pectic Enzymes in Abscission. Plant Physiol. 1960 Mar;35(2):157–162. doi: 10.1104/pp.35.2.157. [DOI] [PMC free article] [PubMed] [Google Scholar]