2',3'-Cyclic nucleotide 3'-phosphodiesterase: a membrane-bound, microtubule-associated protein and membrane anchor for tubulin.
2',3'-Cyclic nucleotide-3'-phosphodiesterase (CNP) is firmly associated with tubulin from brain tissue and FRTL-5 thyroid cells as demonstrated by copolymerization with microtubules through several warm/cold cycles, the presence of CNP activity in purified tubulin preparations, and identical behavior during various extraction procedures. CNP acts as a microtubule-associated protein in promoting microtubule assembly at low mole ratios. This activity resides in the C terminus of the enzyme, which, by itself, promotes microtubule assembly at higher mole ratios. Phosphorylation of CNP interferes with its assembly-promoting activity, as does deletion of the C terminus, which leads to abnormal microtubule distribution in the cell. Submembranous colocalization of the proteins and CNP-dependent microtubule organization suggest that CNP is a membrane-bound microtubule-associated protein that can link tubulin to membranes and may regulate cytoplasmic microtubule distribution.
Bifulco
Maurizio
M
Dipartimento di Scienze Farmaceutiche, Università di Salerno, 84084 Fisciano, Salerno, Italy. maubiful@unina.it
Laezza
Chiara
C
Stingo
Stefania
S
Wolff
J
J
D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000166:cytology; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000737:chemistry / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005822:Genetic Vectors; D005982:Glutathione Transferase / Q000378:metabolism; D049452:Green Fluorescent Proteins; D015151:Immunoblotting; D008164:Luminescent Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D010766:Phosphorylation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013347:Subcellular Fractions; D013961:Thyroid Gland / Q000166:cytology; D013997:Time Factors; D014162:Transfection; D014404:Tubulin / Q000737:chemistry* / Q000378:metabolism
D018076:DNA, Complementary; D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D014404:Tubulin; D049452:Green Fluorescent Proteins; D005982:Glutathione Transferase; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases