Heterologous expression of tomato glycoside hydrolase family 3 α‐L‐arabinofuranosidase/β‐xylosidases in tobacco suspension cultured cells and synergic action of a family 51 isozyme under antisense suppression of the enzyme. Issue 2 (11th July 2013)

• Record Type: Journal Article
• Authors: Tateishi, Akira; Kamiyoshihara, Yusuke; Matsuno, Junko; Miyohashi, Fumika; Shiba, Hajime; Kanayama, Yoshinori; Watanabe, Keiichi; Nomura, Kazunari; Inoue, Hiroaki
• Is Part Of: Physiologia plantarum. Volume 150:Issue 2(2014:Feb.)
• Page Start: 238
• Page End: 251
• Publication Date: 2013-07-11
• Subjects: Plant physiology -- Periodicals; 571.2
• DOI: 10.1111/ppl.12079
• Languages: English
• ISSNs: 0031-9317

Abstract

<abstract abstract-type="main" id="ppl12079-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p id="ppl12079-para-0001">Four cDNA clones (<italic>SlArf/Xyl1‐4</italic>) encoding α‐<sc>l</sc>‐arabinofuranosidase/β‐xylosidase belonging to glycoside hydrolase family 3 were obtained from tomato (<italic>Solanum lycopersicum</italic>) fruit. <italic>SlArf/Xyl1</italic> was expressed in various organs. Its level was particularly high in flower and leaves but low in fruit. <italic>SlArf/Xyl3</italic> was highly expressed in flower. On the contrary, <italic>SlArf/Xyl2</italic> and <italic>4</italic> were expressed in early developmental stage in various organs. Comparison with <italic>SlArf/Xyl4</italic>, <italic>SlArf/Xyl2</italic> expression was observed in earlier stages. The active recombinant proteins were obtained by using BY‐2 tobacco (<italic>Nicotiana tabacum</italic>) suspension cultured cells. The SlArf/Xyl1 and 2 recombinant proteins showed a bi‐functional activity of α‐<sc>l</sc>‐arabinofuranosidase/β‐xylosidase while the SlArf/Xyl4 protein possessed a β‐xylosidase activity predominantly. Neither enzyme activities were detected for the SlArf/Xyl3 protein under the same conditions. Although SlArf/Xyl2 possessed a bi‐functional activity, it preferentially hydrolyzed arabinosyl residues from tomato hemicellulosic polysaccharides. Antisense suppression of <italic>SlArf/Xyl2</italic> resulted in no apparent changes in the enzyme activities, monosaccharide composition or fruit phenotype. Increment of a family 51 α‐<sc>l</sc>‐arabinofuranosidase expression rather than that of family 3 resulted in a restoring the activity in <italic>SlArf/Xyl2</italic>‐suppressed fruit. The ability of recombinant SlArf/Xyl2 to hydrolyze both arabinan and arabinoxylan is nearly identical to that of α‐<sc>l</sc>‐arabinofuranosidases belonging to family 51. Our results suggested that BY‐2 cells are a useful expression system for obtaining active cell wall hydrolyzing enzymes. In addition, an α‐<sc>l</sc>‐arabinofuranosidase activity derived from <italic>SlArf/Xyl2</italic> would be essential in young organ development and the action of the enzyme could be restored by the other enzyme belonging to a different family under a defective condition.</p> </abstract>