EB/RP gene family encodes tubulin binding proteins.
Mutations in the adenomatous polyposis coli (APC) gene are linked to the dysplastic transformation of colorectal polyps and represent an early step in the development of colorectal tumors. Ninety-four percent of all mutations result in the expression of a truncated APC protein lacking the C-terminal region. The C-terminal region of the APC protein may have a tumor suppressor function as its absence appears to be linked to the development of dysplastic lesions. Recently, we discovered and characterized a protein called RP1 which binds specifically to the C-terminal region of the APC protein. We show now that RP1 and the other known members of the EB/RP family (EB1 and RP3) also bind directly to tubulin, both in vitro and in vivo. Immunohistochemical analyses reveal a distinct staining pattern during interphase as well as an association of RP1/EB1 with mitotic microtubule structures. The previously described puncta of the APC protein at the leading edge of membrane protrusions contact microtubule fibers that contain RP1 or EB1.
Juwana
J P
JP
Medical Department I, Saarland University, Homburg, Germany.
Henderikx
P
P
Mischo
A
A
Wadle
A
A
Fadle
N
N
Gerlach
K
K
Arends
J W
JW
Hoogenboom
H
H
Pfreundschuh
M
M
Renner
C
C
D011125:Adenomatous Polyposis Coli / Q000235:genetics; D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D005136:Eye Proteins; D005815:Genetic Code; D006801:Humans; D007150:Immunohistochemistry; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D008938:Mitosis / Q000502:physiology; D008969:Molecular Sequence Data; D005810:Multigene Family; D011506:Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C405804:EB1 microtubule binding proteins; D005136:Eye Proteins; D008869:Microtubule-Associated Proteins; D011506:Proteins; C099929:RPGR protein, human; D014404:Tubulin