Cloning and characterization of two ripening-related strawberry (Fragaria x ananassa cv. Chandler) pectate lyase genes.
Two genomic clones corresponding to putative pectate lyase genes (plA and plB) were isolated and characterized in strawberry (Fragaria x ananassa cv. Chandler). The corresponding ORFs for the plA and plB genes revealed deduced proteins of 451 and 439 amino acids, respectively, that differ from that of the previously isolated strawberry plC gene. Southern blot analysis has shown that while the plB gene is a single copy gene, the plA gene is probably encoded by a small multigene family. By using specific probes corresponding to the untranslated 3' terminal region of the pl genes, and QRT-PCR methodology, the spatio-temporal expression pattern of both strawberry pl genes have been compared with that of the plC gene. The three transcripts were specifically expressed only in fruit and mainly during the ripening stages. Moreover, the expression of the plA and plB genes was induced in green de-achened fruit, but this increase was reduced by the external application of auxins as was the expression of plC. The expression of both pl genes was also strongly reduced in harvested fruit kept in controlled atmosphere (CA) containing high CO(2) levels. Immunolocalization studies using antibodies raised against the strawberry PL proteins placed the proteins in the cell wall of parenchymatic cells of the fruit receptacle. The role of pl genes in cell-wall disassembly and fruit ripening softening is discussed.
Benítez-Burraco
Antonio
A
Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa (Edificio C-6), Campus Universitario de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain.
Blanco-Portales
Rosario
R
Redondo-Nevado
José
J
Bellido
M Luz
ML
Moyano
Enriqueta
E
Caballero
José-L
JL
Muñoz-Blanco
Juan
J
D000595:Amino Acid Sequence; D015139:Blotting, Southern; D002245:Carbon Dioxide / Q000494:pharmacology; D003001:Cloning, Molecular; D031985:Fragaria / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D005638:Fruit / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007150:Immunohistochemistry; D007210:Indoleacetic Acids / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011133:Polysaccharide-Lyases / Q000235:genetics* / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D007210:Indoleacetic Acids; D007527:Isoenzymes; D010940:Plant Proteins; D002245:Carbon Dioxide; D011133:Polysaccharide-Lyases; C023911:pectate lyase