Calcium transport in vesicles from carrot cells: Stimulation by calmodulin and phosphatidylserine. [Daucus carota cv. Danvers]

Conference · Wed May 01 00:00:00 EDT 1991 · Plant Physiology, Supplement; (United States)

OSTI ID:5640533

Hsieh, Wenling; Sze, Heven ^[1]

---

1. Univ. of Maryland, College Park (United States)

The transport properties of Ca-pumping ATPases from carrot (Daucus carota cv. Danvers) tissue culture cells were studied. ATP dependent Ca transport in vesicles that comigrated with an ER marker, was stimulated 3-4 fold by calmodulin. Cyclopiazonic acid (a specific inhibitor of the sarcoplasmic/endoplasmic reticulum Ca-ATPase) partially inhibited oxalate-stimulated Ca transport activity; however, it had little or not effect on calmodulin-stimulated Ca uptake. The results suggested the presence of two types of Ca ATPases, and ER- and a plasma membrane-type. Incubation of membranes with (gamma{sup 32}P)ATP resulted in the formation of a single acyl ({sup 32}P) phosphoprotein of 120 kDa. Formation of this phosphoprotein was dependent on Ca, and enhanced by La {sup 3+}, characteristic of the plasma membrane CaATPase. Acidic phospholipids, like phosphatidylserine, stimulated Ca transport, similar to their effect on the erythrocyte plasma membrane CaATPase. These results would indicate that the calmodulin-stimulated Ca transport originated in large part from a plasma membrane-type Ca pump of 120 kDa.

• DOE Contract Number: FG05-86ER13461
• OSTI ID: 5640533
• Report Number(s): CONF-9107184-; CODEN: PPYSA
• Journal Information: Plant Physiology, Supplement; (United States), Vol. 96:1; Conference: Annual meeting of the American Society of Plant Physiology, Albuquerque, NM (United States), 28 Jul - 1 Aug 1991; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALCIUM
BIOCHEMICAL REACTION KINETICS
PLANT CELLS
PHYSIOLOGY
ATP
ATP-ASE
CALMODULIN
CARROTS
PHOSPHOLIPIDS
PHOSPHORUS 32
ACID ANHYDRASES
ALKALINE EARTH METALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
DAYS LIVING RADIOISOTOPES
ELEMENTS
ENZYMES
ESTERS
FOOD
HYDROLASES
ISOTOPES
KINETICS
LIGHT NUCLEI
LIPIDS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
METALS
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOHYDROLASES
PHOSPHORUS ISOTOPES
PLANTS
PROTEINS
RADIOISOTOPES
REACTION KINETICS
VEGETABLES
550200* - Biochemistry