Institute for Integrative Genome Biology


Timothy CloseTimothy Close

Professor and Geneticist

Mailing Address:

Botany and Plant Sciences
Batchelor Hall /4157
University of California
Riverside, CA 92521

Phone: (951) 827-3318
Fax: (951) 827-4437
Email: timothy.close@ucr.edu

UCR Living the Promise Profile


PhD 1982 University of California, Davis
MS 1979 University of California, Davis
BA 1976 University of California, San Diego

College/Division Affiliation:

College of Natural and Agricultural Sciences

Areas Of Expertise:

Crop Plant Genomics and Bioinformatics; High Density Genetic Linkage Maps and Marker Assisted Selection; Barley, Citrus, Cowpea, Rice, Wheat; Abiotic and Biotic Stress Regulated Genes and Proteins; Application of Transcriptome Analyses to Biomarker Development for Citrus

Awards / Honors:

2009  AAAS Fellow (American Association for the Advancement of Science)
1992-98  National Science Foundation Divisional Young Investigator

Research Summary:

The goals in my laboratory are to:
  1. Create and utilize genomic resources for research and teaching, and conduct educational outreach in crop plant genomics
  2. Promote environmental tolerance in plants through genetics and efficient cultural and post-harvest practices
  3. Develop biomarkers including SNPs and immunological assays from genomic studies of plant traits
  4. Determine the properties of plant stress proteins to understand mechanisms

The research goals in abiotic stress are unified by the question, "What are the fundamental biochemical processes within which there exists genetic diversity related to tolerance, particularly of low temperature, drought, and salinity?" One example is the family of proteins known as "dehydrins" (a.k.a. LEAD11). Dehydrins are "intrinsically unstructured proteins" that are produced in plants in response to low non-freezing temperatures or any environmental influence with a dehydration component, including seed development, drought stress, freeze-thaw, and osmotic stress. We purified these proteins from plants and genetically engineered Escherichia coli strains for in vitro studies, and found that dehydrins associate with unilamellar vesicles containing anionic phospholipids (Koag et al. 2003). We demonstrated in the 1990's by immunocytochemical methods that plant dehydrins can be present in the nucleus, and are associated with endomembrane-rich areas of the cytoplasm. We found 13 dehydrin (Dhn) genes in barley, dispersed at eight genetic map locations on five chromosomes. Some of these locations, as well as Dhn loci in maize and other plants, seem to coincide with QTL for low temperature or drought tolerance. The Vigna unguiculata (cowpea) Dhn1 gene, associated with chilling tolerance during seedling emergence, is one such example (Ismail et al. 1999).

My group is active in Triticeae (wheat, barley, rye), Citrus, rice and cowpea genomics. This includes library production, EST assemblies, content definition for barley and citrus microrarrays, development of software (HarvEST) for EST database browsing. It also includes genetic mapping in barley, citrus, cowpea, rice and wheat, and microarray-based transcriptome analyses of abiotic stresses in rice and barley, as well as a number of traits relevant to citrus such as easy-peeling, the effect of storage on flavor, citrus tristeza virus response and others. The research is currently funded by grants from the National Science Foundation Plant Genome Research Program, USDA Coordinated Agricultural Project, University of California Discovery Grants Program, California Citrus Research Board, the Generation Challenge Program and the Agricultural Experiment Station.

Press Releases:

Selected Publications:

List of publications from PubMed

Lab Personnel: 

Fenton, Raymond D
Staff Research Associate — New cDNA Libraries; Combinatorial Pooling; Curation of Barley Genetic Resources; Purification and Biochemical Analyses of Dehydrins
Wanamaker, Steve
Programmer — HarvEST software (Windows and online)
Duma, Denisa
Graduate Student Researcher (Computer Science) — Barley and Cowpea Genome Sequencing and Assembly
Pottorff, Marti
Graduate Student Researcher (Plant Biology) — Crop Plant Genomics & Bioinformatics; Genetics of Fusarium and Macrophomina Resistance inCowpea
Lucas, Mitch
Graduate Student Researcher (Genetics, Genomics & Bioinformatics) — Cowpea Genetics and  Breeding
Manley, Eric
Community College Student Researcher — Cowpea Chilling Tolerance during Seedling Emergence
Alpert, Matt
Undergraduate Student Researcher (Computer Science) — Barley and Cowpea Genome Sequencing and Assembly
Guo, Yi-Ning
Undergraduate Student Researcher — Cowpea Chilling Tolerance during Seedling Emergence
Woods, Victoria
Undergraduate Student Researcher — AssociationG enetics and Candidate Gene Analysis for Various Traits of Cowpea

More Information

General Campus Information

University of California, Riverside
900 University Ave.
Riverside, CA 92521
Tel: (951) 827-1012

Career OpportunitiesUCR Libraries
Campus StatusDirections to UCR

Genomics Information

Institute of Integrative Genome Biology
2150 Batchelor Hall

Tel: (951) 827-7177
E-mail: Aurelia Espinoza, Managing Director