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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Crop Improvement and Genetics Research » Research » Publications at this Location » Publication #235750

Title: The complete sequence of the plastid genome of Parthenium argentatum is similar to those of other Asteraceae species and provides DNA barcodes that differentiate species and lines

Author
item KUMAR, SHASHI
item Whalen, Maureen
item Hahn, Frederick
item McMahan, Colleen
item CORNISH, KATRINA

Submitted to: Biomed Central (BMC) Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/16/2009
Publication Date: 11/17/2009
Citation: Kumar, S., Whalen, M.C., Hahn, F.M., Mcmahan, C.M., Cornish, K. 2009. The complete sequence of the plastid genome of Parthenium argentatum is similar to those of other Asteraceae species and provides DNA barcodes that differentiate species and lines. Biomed Central (BMC) Plant Biology. 9:131.Available: http://www.biomedcentral.com/1471-2229-9-131.

Interpretive Summary: Parthenium argentatum, guayule, is an industrial crop that produces latex, which was recently commercialized as a source of latex rubber safe for people with Type I latex allergy. The complete chloroplast genome of guayule was sequenced. The sequence provided important information that was used for analysis of evolutionary relationships, as well as for genetic engineering strategies. Comparison to the sequences of chloroplast genomes from three other members of the plant family Asteraceae, Lactuca sativa (lettuce), Guitozia abyssinica (niger) and Helianthus annuus (sunflower) revealed that the chloroplast genome of guayule is overall more closely related to that of sunflower, followed by niger and then lettuce. The DNA barcoding study forms the foundation for genetic identification of commercially significant lines of guayule that are important for producing latex. The availability of the complete plastid genome sequence will facilitate improved transformation efficiency of the guayule chloroplast.

Technical Abstract: Parthenium argentatum, guayule, is an industrial crop that produces latex, which was recently commercialized as a source of latex rubber safe for people with Type I latex allergy. The complete plastid genome of P. argentatum was sequenced. The sequence provided important information used for phylogenetic analyses, as well as for genetic engineering strategies. Comparison to the sequences of plastid genomes from three other members of the Asteraceae, Lactuca sativa, Guitozia abyssinica and Helianthus annuus revealed details of the evolution of the four genomes. The sequence of the P. argentatum plastid genome allowed development of a chloroplast specific DNA barcode for analyzing phylogenetic relationships among and within Parthenium species. The complete plastid genome of P. argentatum is 152,803 bp. Based on the overall comparison of individual protein coding genes with those in L. sativa, G. abyssinica and H. annuus, as well as phylogenetic analysis of the matK gene, we demonstrate that the P. argentatum chloroplast genome sequence is most closely related to that of H. annuus. Similar to chloroplast genomes in two out of three subfamilies in the Asteraceae, the plastid genome of P. argentatum has a large 23 kb inversion. In addition, there is a smaller 3.4 kb inversion, within the large inversion. These two features are also present in plastid genomes of G. abyssinica, L. sativa and H. annuus. Phylogenetic analyses using the matK and psbA-trnH spacer chloroplast DNA barcodes indicate four of the five Parthenium species tested, P. tomentosum, P. hysterophorus, P. integrilulium and P. schottii, can be genetically differentiated from P. argentatum. In addition, we demonstrate sub-species differentiation within P. argentatum. The genome sequence of the P. argentatum chloroplast will enrich the sequence resources of plastid genomes in commercial crops, as well as contribute to evolutionary studies in the Asteraceae. The availability of the complete plastid genome sequence will facilitate improved transformation efficiency by using the precise sequence of endogenous flanking sequences and regulatory elements in chloroplast transformation vectors. The DNA barcoding study forms the foundation for genetic identification of commercially significant lines of P. argentatum that are important for producing latex.