ORCID Profile
0000-0003-0119-7012
Current Organisations
Flinders University
,
CSIRO
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Publisher: Springer Science and Business Media LLC
Date: 21-03-2019
DOI: 10.1007/S00122-019-03329-W
Abstract: Elite wheat pollinators are critical for successful hybrid breeding. We identified Rht-B1 and Ppd-D1 loci affecting multiple pollinator traits and therefore represent major targets for improving hybrid seed production. Hybrid breeding has a great potential to significantly boost wheat yields. Ideal male pollinators would be taller in stature, contain many spikelets well-spaced along the spike and exhibit high extrusion of large anthers. Most importantly, flowering time would match with that of the female parent. Available genetic resources for developing an elite wheat pollinator are limited, and the genetic basis for many of these traits is largely unknown. Here, we report on the genetic analysis of pollinator traits using biparental mapping populations. We identified two anther extrusion QTLs of medium effect, one on chromosome 1BL and the other on 4BS coinciding with the semi-dwarfing Rht-B1 locus. The effect of Rht-B1 alleles on anther extrusion is genotype dependent, while tall plant Rht-B1a allele is consistently associated with large anthers. Multiple QTLs were identified at the Ppd-D1 locus for anther length, spikelet number and spike length, with the photoperiod-sensitive Ppd-D1b allele associated with favourable pollinator traits in the populations studied. We also demonstrated that homeoloci, Rht-D1 and Ppd-B1, influence anther length among other traits. These results suggest that combinations of Rht-B1 and Ppd-D1 alleles control multiple pollinator traits and should be major targets of hybrid wheat breeding programs.
Publisher: Elsevier BV
Date: 2013
Publisher: Springer Science and Business Media LLC
Date: 2007
Publisher: Springer Science and Business Media LLC
Date: 02-2015
Publisher: Wiley
Date: 11-04-2019
DOI: 10.1111/PBI.13106
Publisher: Wiley
Date: 08-03-2023
DOI: 10.1111/NPH.18801
Abstract: Many plant species can give rise to embryos from somatic cells after a simple hormone treatment, illustrating the remarkable developmental plasticity of differentiated plant cells. However, many species are recalcitrant to somatic embryo formation for unknown reasons, which poses a significant challenge to agriculture, where somatic embryogenesis is an important tool to propagate desired genotypes. The micro‐RNA394 (miR394) promotes shoot meristem maintenance in Arabidopsis thaliana , but the underlying mechanisms have remained elusive. We analyzed whether miR394 affects indirect somatic embryogenesis and determined the transcriptome of embryogenic callus upon miR394‐enhanced somatic embryogenesis. We show that ectopic miR394 expression enhances somatic embryogenesis in the recalcitrant L er accession when co‐expressed with the transcription factor WUSCHEL (WUS) and that miR394 acts in this process through silencing the target LEAF CURLING RESPONSIVENESS (LCR). Furthermore, we show that higher endogenous miR394 levels are required for the elevated embryogenic potential of the Columbia accession compared with L er , providing a mechanistic explanation for this natural variation. Our transcriptional analysis provides a framework for miR394 function in regulating pluripotency by expanding WUS‐mediated direct transcriptional repression.
Publisher: The Company of Biologists
Date: 09-2008
DOI: 10.1242/DEV.023648
Abstract: Stem cells are maintained in an undifferentiated state by signals from their microenvironment, the stem cell niche. Despite its central role for organogenesis throughout the plant's life, little is known about how niche development is regulated in the Arabidopsis embryo. Here we show that, in the absence of functional ZWILLE (ZLL), which is a member of the ARGONAUTE (AGO) family, stem cell-specific expression of the signal peptide gene CLAVATA3 (CLV3) is not maintained despite increased levels of the homeodomain transcription factor WUSCHEL (WUS), which is expressed in the organising centre (OC) of the niche and normally promotes stem cell identity. Tissue-specific expression indicates that ZLLacts to maintain the stem cells from the neighbouring vascular primordium,providing direct evidence for a non-cell-autonomous mechanism. Furthermore,mutant and marker gene analyses suggest that during shoot meristem formation, ZLL functions in a similar manner but in a sequential order with its close homologue AGO1, which mediates RNA interference. Thus, WUS-dependent OC signalling to the stem cells is promoted by AGO1 and subsequently maintained by a provascular ZLL-dependent signalling pathway.
Publisher: Elsevier BV
Date: 06-2011
DOI: 10.1016/J.PBI.2011.03.002
Abstract: Abiotic stress tolerance is complex, but as phenotyping technologies improve, components that contribute to abiotic stress tolerance can be quantified with increasing ease. In parallel with these phenomics advances, genetic approaches with more complex genomes are becoming increasingly tractable as genomic information in non-model crops increases and even whole crop genomes can be re-sequenced. Thus, genetic approaches to elucidating the molecular basis to abiotic stress tolerance in crops are becoming more easily achievable.
Publisher: Elsevier BV
Date: 02-2017
DOI: 10.1016/J.DEVCEL.2017.01.002
Abstract: The establishment of pluripotent stem cells is a key event during plant and animal embryogenesis, but the underlying mechanisms remain enigmatic. We show that in the flowering plant Arabidopsis thaliana, expression of the shoot meristem stem cell marker CLV3 becomes detectable in transition stage embryos. Surprisingly, the key regulator of stem cell homeostasis WUSCHEL (WUS) is expressed but dispensable for stem cell initiation. Rather, the WUS paralog WOX2, a regulator of embryo patterning initiated in the zygote, functions in this process by shielding stem cell progenitors from differentiation. WOX2 upregulates HD-ZIP III transcription factors required for shoot identity and balances cytokinin versus auxin hormone pathways, revealing that classical plantlet regeneration procedures recapitulate the natural induction mechanism. Our findings link transcriptional regulation of early embryo patterning to hormonal control of stem cell initiation and suggest that similar strategies have evolved in plant and animal stem cell formation.
Publisher: Elsevier BV
Date: 02-2007
DOI: 10.1016/J.YDBIO.2006.09.013
Abstract: During anther development a series of cell specification events establishes the male gametophyte and the surrounding sporophytic structure. Here we show that the homeobox gene WUSCHEL, originally identified as a central regulator of stem cell maintenance, plays an important role in cell type specification during male organogenesis. WUS expression is initiated very early during anther development in the precursor cells of the stomium and terminates just before the stomium cells enter terminal differentiation. At this stage the stomium cells and the neighboring septum cells that separate the pollen sacs undergo typical cell wall thickening and degenerate which leads to rupture of the anther and pollen release. In wus mutants, neither stomium cells nor septum cells differentiate or undergo cell death and degenerate. As a consequence, the anther stays intact and pollen is not released. CLAVATA3 which is activated by WUS in stem cell maintenance, is not activated in anthers indicating a novel pathway regulated by WUS. Comparing WUS function in stem cell maintenance and sexual organ development suggests that WUS expressing cells represent a conserved signaling module that regulates behavior and communication of undifferentiated cells.
Publisher: Springer Science and Business Media LLC
Date: 12-2013
Publisher: Springer Science and Business Media LLC
Date: 12-2018
Publisher: Springer Science and Business Media LLC
Date: 11-10-2017
DOI: 10.1038/S41467-017-00945-2
Abstract: The current rate of yield gain in crops is insufficient to meet the predicted demands. Capturing the yield boost from heterosis is one of the few technologies that offers rapid gain. Hybrids are widely used for cereals, maize and rice, but it has been a challenge to develop a viable hybrid system for bread wheat due to the wheat genome complexity, which is both large and hexaploid. Wheat is our most widely grown crop providing 20% of the calories for humans. Here, we describe the identification of Ms1 , a gene proposed for use in large-scale, low-cost production of male-sterile ( ms ) female lines necessary for hybrid wheat seed production. We show that Ms1 completely restores fertility to ms1d , and encodes a glycosylphosphatidylinositol-anchored lipid transfer protein, necessary for pollen exine development. This represents a key step towards developing a robust hybridization platform in wheat.
Publisher: Springer New York
Date: 2014
DOI: 10.1007/978-1-4939-0446-4_5
Abstract: High-resolution melting (HRM) analysis is a simple, closed tube, post-PCR method used to identify genetic variation. The method is highly sensitive and can discriminate DNA sequence variants based on length (such as insertions or deletions), composition (such as single nucleotide polymorphisms, i.e., SNP) or strand complementarity (such as heterozygous or homozygous material). The technique involves PCR lification of a target sequence in the presence of a fluorescent double-stranded DNA (dsDNA) binding dye, melting of the fluorescent licons, and subsequent interpretation of melt curve profiles. Here, we describe general considerations for assay design, PCR lification, and HRM analysis.
Location: Australia
No related grants have been discovered for Elise Tucker.