Format

Send to

Choose Destination
BMC Plant Biol. 2006 Mar 14;6:6.

Gene amplification of the Hps locus in Glycine max.

Author information

1
Agriculture and Agri-Food Canada, London, Ontario, N5V 4T3, Canada. gijzenm@agr.gc.ca

Abstract

BACKGROUND:

Hydrophobic protein from soybean (HPS) is an 8 kD cysteine-rich polypeptide that causes asthma in persons allergic to soybean dust. HPS is synthesized in the pod endocarp and deposited on the seed surface during development. Past evidence suggests that the protein may mediate the adherence or dehiscence of endocarp tissues during maturation and affect the lustre, or glossiness of the seed surface.

RESULTS:

A comparison of soybean germplasm by genomic DNA blot hybridization shows that the copy number and structure of the Hps locus is polymorphic among soybean cultivars and related species. Changes in Hps gene copy number were also detected by comparative genomic DNA hybridization using cDNA microarrays. The Hps copy number polymorphisms co-segregated with seed lustre phenotype and HPS surface protein in a cross between dull- and shiny-seeded soybeans. In soybean cultivar Harosoy 63, a minimum of 27 +/- 5 copies of the Hps gene were estimated to be present in each haploid genome. The isolation and analysis of genomic clones indicates that the core Hps locus is comprised of a tandem array of reiterated units, with each 8.6 kb unit containing a single HPS open reading frame.

CONCLUSION:

This study shows that polymorphisms at the Hps locus arise from changes in the gene copy number via gene amplification. We present a model whereby Hps copy number modulates protein expression levels and seed lustre, and we suggest that gene amplification may result from selection pressures imposed on crop plants.

PMID:
16536872
PMCID:
PMC1421400
DOI:
10.1186/1471-2229-6-6
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center