Constitutive expression of CaSRP1, a hot pepper small rubber particle protein homolog, resulted in fast growth and improved drought tolerance in transgenic Arabidopsis plants.
Transient and long-term shortages of fresh water are major adverse environmental factors that cause dramatic reductions in crop production and distribution globally. In this study, we isolated a full-length CaSRP1 (Capsicum annuum stress-related protein 1) cDNA, which was rapidly induced by dehydration in hot pepper plants. The predicted CaSRP1 protein sequence exhibited significant amino acid identity to putative stress-related proteins and the small rubber particle protein (SRPP) found in rubber trees (Hevea brasiliensis). To study the cellular functions of CaSRP1, transgenic Arabidopsis plants (35S:CaSRP1) that constitutively expressed the CaSRP1 gene were constructed. Overexpression of CaSRP1 resulted in enhanced root and shoot growth and earlier bolting in the transgenic plants relative to wild-type plants. In addition, 35S:CaSRP1 overexpressors exhibited enhanced tolerance to drought stress as compared to the control plants. These results suggest that CaSRP1 plays dual functions as a positive factor for tissue growth and development and for drought-defensive responses. A possible cellular function of SRPP homologs in non-rubber-producing plants in relation to drought stress tolerance is discussed.
Kim
Eun Yu
EY
Department of Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, Korea.
Seo
Young Sam
YS
Lee
Hanna
H
Kim
Woo Taek
WT
D000222:Adaptation, Physiological / Q000502:physiology*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D001483:Base Sequence; D002212:Capsicum / Q000235:genetics*; D017931:DNA Primers; D018076:DNA, Complementary; D055864:Droughts; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; D018076:DNA, Complementary; D010940:Plant Proteins