Noncytoplasmic and filamentous appearance of calbindin-D28k and tubulin in double, indirect immunofluorescent staining of embryonic chick tissue.
Double indirect immunofluorescent labeling of embryonic chick tissue was undertaken for the vitamin D-induced calcium binding protein, calbindin-D28k, and microtubules. Immunoreactivities for both calbindin-D28k and tubulin were found to exhibit a filamentous staining pattern in mesonephros, metanephros, intestine, and brain. In the intestine, staining was absent at 19 days, while immunolabeling of tubulin became evident at 20 days, and both antigens were present in 21-day tissue. In intestinal epithelium, as well as in 10-day metanephros, it was strikingly evident that cells either stained for both antigens or were negative for both calbindin-D28k and tubulin. In 11-12-day metanephros, an increased number of cells with both immunoreactivities were found. In 15-17-day brain, tubulin was evident within all cells but stained most intensely in Purkinje cells which were also positive for calbindin-D28k. Mesonephros from 4-5-day embryos revealed immunolabeling of both tubulin and the calcium binding protein. A statistical analysis of the various cell types revealed that the vast majority contained either both antigens or neither of the immunoreactivities. Of the more than 600 cells scored, none were found to be positive for calbindin-D28k, while at the same time negative for tubulin. It is concluded that calbindin-D28k exhibits a noncytoplasmic distribution in all tissues tested and that the filamentous appearance may reflect localization of the antigen in tubulo-vesicular organelles associated with cytoskeleton.
Nemere
I
I
Division of Biomedical Sciences, University of California, Riverside 92521.
Opperman
L A
LA
Ross
F P
FP
Norman
A W
AW
D000818:Animals; D001921:Brain / Q000196:embryology / Q000648:ultrastructure; D001923:Brain Chemistry; D064026:Calbindins; D002642:Chick Embryo; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D007422:Intestines / Q000737:chemistry* / Q000196:embryology / Q000648:ultrastructure; D007668:Kidney / Q000737:chemistry* / Q000196:embryology / Q000648:ultrastructure; D008650:Mesonephros / Q000737:chemistry* / Q000648:ultrastructure; D008870:Microtubules / Q000648:ultrastructure; D015388:Organelles / Q000737:chemistry / Q000648:ultrastructure; D064030:S100 Calcium Binding Protein G / Q000032:analysis*; D014404:Tubulin / Q000032:analysis*
D064026:Calbindins; D064030:S100 Calcium Binding Protein G; D014404:Tubulin