HOMEPRODUCTSSERVICESCOMPANYCONTACTFAQResearchDictionaryPharmaMobileSign Up FREE or Login

Expression of the high capacity calcium-binding domain of calreticulin increases bioavailable calcium stores in plants.

Abstract
Modulation of cytosolic calcium levels in both plants and animals is achieved by a system of Ca2+-transport and storage pathways that include Ca2+ buffering proteins in the lumen of intracellular compartments. To date, most research has focused on the role of transporters in regulating cytosolic calcium. We used a reverse genetics approach to modulate calcium stores in the lumen of the endoplasmic reticulum. Our goals were two-fold: to use the low affinity, high capacity Ca2+ binding characteristics of the C-domain of calreticulin to selectively increase Ca2+ storage in the endoplasmic reticulum, and to determine if those alterations affected plant physiological responses to stress. The C-domain of calreticulin is a highly acidic region that binds 20-50 moles of Ca2+ per mole of protein and has been shown to be the major site of Ca2+ storage within the endoplasmic reticulum of plant cells. A 377-bp fragment encoding the C-domain and ER retention signal from the maize calreticulin gene was fused to a gene for the green fluorescent protein and expressed in Arabidopsis under the control of a heat shock promoter. Following induction on normal medium, the C-domain transformants showed delayed loss of chlorophyll after transfer to calcium depleted medium when compared to seedlings transformed with green fluorescent protein alone. Total calcium measurements showed a 9-35% increase for induced C-domain transformants compared to controls. The data suggest that ectopic expression of the calreticulin C-domain increases Ca2+ stores, and that this Ca2+ reserve can be used by the plant in times of stress.
AuthorsSarah E Wyatt, Pei-Lan Tsou, Dominique Robertson
JournalTransgenic research (Transgenic Res) Vol. 11 Issue 1 Pg. 1-10 (Feb 2002) ISSN: 0962-8819 [Print] Netherlands
PMID11874098 (Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)
Chemical References
  • Calcium-Binding Proteins
  • Calreticulin
  • Luminescent Proteins
  • Ribonucleoproteins
  • Green Fluorescent Proteins
  • Calcium
Topics
  • Agrobacterium tumefaciens (genetics)
  • Arabidopsis (genetics, growth & development)
  • Biological Availability
  • Calcium (metabolism)
  • Calcium-Binding Proteins (chemistry, metabolism)
  • Calreticulin
  • Genetic Vectors
  • Green Fluorescent Proteins
  • Luminescent Proteins (genetics)
  • Phenotype
  • Plants, Genetically Modified
  • Ribonucleoproteins (chemistry, metabolism)
  • Zea mays (genetics, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!


Choose Username:
Email:
Password:
Verify Password: