Reyes Genetics Lab
The 'Ten billion people question' (10BPQ) posts an enormous challenge of how to maximize crop genetic gains amidst
the rapid population growth and burgeoning effects of climate change. Developing the
next generation of climate-resilient crops by maximizing the potential of what has
been engineered, tested, and optimized by evolution (i.e. germplasm) would be critical
in addressing this grand challenge to 21st century agriculture. On top of what has
already been achieved during the last century of crop genetic improvements by conventional
plant breeding, genomics, and biotechnology, any further enhancements in stress tolerance
and yield potentials of major food crops will have to rely on the ability of modern
genetic technology to create novel phenotypes or physiological attributes that were
not achieved during the first Green Revolution during the 1960's.
The genus Oryza includes the Asian (O. sativa) and African (O. glaberrima) cultivated rice, and 22 wild species that collectively span ~15 million years of
speciation and ~4,000 years of domestication history. The genus represents a wide
spectrum of ecological niches whose real potential in stress tolerance breeding is
just beginning to be unlocked through the power of genomics-enabled hypothesis-testing.
With a long-term goal of contributing a possible component of the solution to the
10BPQ, current research in my laboratory is using the more exotic cultivated and wild
Oryza as genetic model system to address the hypothesis that:
Transgressive traits for stress (temperature, drought, salinity) tolerance are the
outcomes of regulatory network rewiring. They are manifestations of novel patterns
of gene expression mediated by reconfigured genomic and epigenomic landscapes as an
outcome of recombination between diverse genomes.
Transgressive segregation is a phenomenon wherein a minority of the recombinant progenies
derived from two genetically diverse parents exhibit quantitative phenotypic variation
that are beyond the range of the two parents. Genetics alone has not been able to
fully explain the mechanistic basis of this phenomenon. Given this, the goal of my
research program is to examine the phenomenon of network rewiring in genetic populations
of rice exhibiting transgressive segregation for abiotic stress tolerance, by probing
into the different facets of its complexity both at the level of genetic and epigenetic
regulation. This research is based on the assumptions that:
- Ideal or non-ideal complementation and/or epistatic interaction could cause transgressive phenotypes. This happens when multiple hubs of regulatory networks and their downstream targets from either parents are brought together in the same genetic background by recombination, hence regulon complementation.
- Transgressive phenotypes (either positive or negative) may be configured by epigenomic changes mediated by non-coding regulatory RNA expression. These events lead to post-transcriptional gene silencing (PTGS) by miRNA, and/or transcriptional gene silencing (TGS) by RNA-directed DNA methylation, leading to network rewiring.
- Transgressive phenotypes (either positive or negative) may be the result of different levels of interactions among quantitative trait loci (QTL), and between QTL and genetic background by virtue of mechanisms that involve both genetic and epigenetic regulation. These interactions may lead to either synergistic, complementary or antagonistic effects.
By comparative genomic, regulomic, and epigenomic analyses coupled with functional
validation by transgenic and modern genome editing approaches, we aim to uncover patterns
of genetic and epigenetic changes that reconfigure physiological and/or biochemical
networks in transgressive individuals derived from genetically diverse crosses across
cultivated and wild Oryza. With these strategies, we hope to explain the regulatory
mechanisms behind the gain or loss of phenotypic attributes mediated by genome and
epigenome shuffling that may be triggered by recombination.
Capitalizing on the transformative knowledge resulting from the investigation of a
tractable evolutionary and genetic model system such as Oryza, we are also extending
the same research paradigms to do translational research on crop(s) of economic importance
to the water-limited agroecosystem of west Texas. Current focus of this part of my
research program is to mine the natural gene pool of the cultivated Gossypium (cotton)
for both major and cryptic morpho-physiometric components contributing to overall
potentials for salinity and drought tolerance using similar omics-enabled research
paradigm that we have established in the Oryza project. In the long term, we aim to
use the information generated from the omics-enabled research to model the ideal combinations
of major and cryptic physiological traits and their underlying genomic and epigenomic
mechanisms.
Dr. Benildo de los Reyes
Professor of Plant Genomics,
Bayer Crop Science Endowed Chair,
Graduate Programs Director
Department of Plant and Soil Science
Texas Tech University
Experimental Sciences Building
Room 215, Mail Stop 2122
Lubbock, TX 79409-2122
Phone: +1 (806) 834-6421;
Fax: 806-742-0775
Email: benildo.reyes@ttu.edu
Department of Plant and Soil Science
-
Address
Texas Tech University, Department of Plant and Soil Science, Box 42122, Lubbock, TX 79409 -
Phone
806.742.2838 -
Email
psstechsupport@ttu.edu