Please use this identifier to cite or link to this item:
Type: Thesis
Title: Regulation of (1,3;1,4)-beta-glucan synthesis in barley (Hordeum vulgare L.) endosperm and leaf tissues.
Author: Wong, Sie-Chuong
Issue Date: 2015
School/Discipline: School of Agriculture, Food and Wine
Abstract: This project was carried out to explore the regulatory mechanism for (1,3;1,4)-β-glucan synthesis in barley (Hordeum vulgare L.) in both endosperm and leaf tissues. For the grain (1,3;1,4)-β-glucan content regulation study, transcriptional profiles of candidate genes involved in (1,3;1,4)-β-glucan synthesis and degradation, from the developing barley endosperm, were compared across parental lines that had been previously used for grain (1,3;1,4)-β-glucan QTL studies. Correspondence between differences in transcript levels of selected genes and the QTL detected in parental lines was analysed. In the high (1,3;1,4)-β-glucan parent of a mapping population with a grain (1,3;1,4)-β-glucan QTL near/at the location of the HvCslF6 gene, HvCSLF6 transcript levels increased sharply late in endosperm development. In contrast, HvCslF6 transcript levels did not differ between parents of a mapping population in which no grain (1,3;1,4)-β-glucan QTL had been mapped near/at the HvCslF6 gene. Co-transcription of a β-glucan exo-glucanase gene, HvExoIV gene with HvCslF9 early in endosperm development and with HvCslF6 late in endosperm development indicated that HvEXOIV could be involved in (1,3;1,4)-β-glucan synthesis. It has been reported that leaf (1,3;1,4)-β-glucan is degraded when plants are incubated in the dark for prolonged periods and is re-synthesized upon re-exposure to a normal day/night cycle. Thus, to investigate the regulation of leaf (1,3;1,4)-β-glucan, the transcript levels of (1,3;1,4)-β-glucan synthase genes and related genes were profiled during (1,3;1,4)-β-glucan mobilization upon dark incubation. Some of the genes that responded to prolonged dark incubation showed diurnal transcription patterns, even in continuous darkness. Among the (1,3;1,4)-β-glucan synthase candidate genes, only HvCslH1 was up-regulated upon dark incubation. Its transcripts quickly returned to control levels upon re-exposure to the normal day/night cycle. None of the (1,3;1,4)-β-glucan synthase genes were up-regulated upon re- exposure to normal day/night cycles. Consistent with what was observed for HvExoIV, HvCslF6 and HvCslF9 in developing endosperm, HvExoIV seemed to exhibit co-transcription gene with the HvCslH1.
Advisor: Mather, Diane Elizabeth
Fincher, Geoffrey Bruce
Dissertation Note: Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2015
Keywords: (1,3;1,4)-beta-glucan; HvCslF6; HvExoIV; barley; endosperm
Provenance: This electronic version is made publicly available by the University of Adelaide in accordance with its open access policy for student theses. Copyright in this thesis remains with the author. This thesis may incorporate third party material which has been used by the author pursuant to Fair Dealing exceptions. If you are the owner of any included third party copyright material you wish to be removed from this electronic version, please complete the take down form located at:
Appears in Collections:Research Theses

Files in This Item:
File Description SizeFormat 
01front.pdf392.29 kBAdobe PDFView/Open
02whole.pdf2.87 MBAdobe PDFView/Open
  Restricted Access
Library staff access only387 kBAdobe PDFView/Open
  Restricted Access
Library staff access only2.88 MBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.