Identification and characterization of polyphosphoinositides in the tonoplast membrane

Journal Article · Sat Apr 01 04:00:00 EST 1989 · Plant Physiology, Supplement; (USA)

OSTI ID:6945360

Cho, Myeon; Memon, A R; Boss, W F ^[1]

---

1. North Carolina State Univ., Raleigh (USA)

In vitro data indicate that the tonoplast membrane is the major target site for IP{sub 3} action and Ca{sup +2} is released from this compartment. If this is true, then several questions arise: (1) Is the plasma membrane or tonoplast the source of IP{sub 3} (2) If the plasma membrane is the source of IP{sub 3}, how does IP{sub 3} get to the vacuole In this connection, the results from in vivo labeling of carrot cells with ({sup 3}H) inositol show that the major phospholipid components in the tonoplast are PI and lysoPIP. In vitro phosphorylation studies using ({gamma}-{sup 32}P)ATP indicate that PI kinase is present in the tonoplast membrane even though PIP was not detected with inositol labeling. If PIP and PIP{sub 2} are not present in the tonoplast, then IP{sub 3} must diffuse or be transported from the plasma membrane. Since IP{sub 3} is rapidly metabolized by cytosolic phosphatases there may be an IP{sub 3}-sensitive calcium store other than the vacuole closely associated with the plasma membrane.

• OSTI ID: 6945360
• Journal Information: Plant Physiology, Supplement; (USA), Journal Name: Plant Physiology, Supplement; (USA) Vol. 89:4; ISSN PPYSA; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ATP
CARBOHYDRATES
CARROTS
CELL CONSTITUENTS
CELL MEMBRANES
CHEMICAL REACTIONS
ESTERS
FOOD
HYDROGEN COMPOUNDS
INOSITOL
INOSITOLS
ISOTOPE APPLICATIONS
LIPIDS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
MEMBRANES
MONOSACCHARIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PHOSPHORYLATION
PHYSIOLOGY
PLANT CELLS
PLANTS
SACCHARIDES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VEGETABLES