Cell Communication during Aggregation and Development of the Cellular Slime Mould Distyostelium discoideum.
Abstract
The role for folates and pterins as potential morphogens during tipped aggregate formation was studied. A revised folate binding assay was employed to demonstrate the presence of folate receptors on vegetative Dictyostelium discoideum amoebae. These receptors are present at 45,000 per cell and function as a single class that bind folate and deaminofolate (DAFA) with equal affinity (dissociation constant = 300nM). A pool of receptors was found attached to the cytoskeletons of vegetative amoebae and these receptors (10,000 sites/cell, Kd 480nM) remain associated with the cytoskeleton through the first 12 hr of development. A role for te cytoskeleton in receptor modulation during signal transduction is postulated. Competitive binding studies with 21 folate a pterin analogues revealed that the folate receptor shows a high degree of specificity for the intact folate moiety. The folate-induced, rapid and transient accumulation of actin in the Triton X-100 insoluble cytoskeletons correlates with tipped aggregate formation in developing Dictyostelium cells. A surprising role for L-monapterin as an active chempoattractant during tipped aggregate formation is described.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1985
- Accession Number
- ADA158157
Entities
People
- H. S. Tillinghast Jr
Organizations
- Air Force Institute of Technology