Phenotype Image Detail

Image

Caption

Defective organization and polarization of osteoblasts in Col12a1^tm1Debi/Col12a1^tm1Debi (Col12a1-/-) bone. Osteoblast polarization was analyzed by the distribution of nucleus, Golgi apparatus, and F-actin staining with confocal fluorescence microscopy. (A) Wild-type (WT) osteoblasts (OB) in an epithelioid arrangement are well organized into a layer between the periosteum (PO) and cortical bone (CB), and F-actin fibers (green) are highly enriched in regions of the osteoblasts, which face the periosteum and cortical bone (white arrows). (B) In contrast, mutant osteoblasts are not well organized between the periosteum and cortical bone, and F-actin fibers appear to form aggregates distributed randomly within osteoblasts (arrows). (C) WT osteoblasts exhibit a polarized distribution of the Golgi apparatus (red) and the nucleus (blue). Most Golgi reactivity is localized toward the bone matrix (arrows), whereas the nuclei were positioned to the opposite side. (D) Mutant osteoblasts also fail to show apolarized distribution of Golgi and nucleus. It is noticeable that the F-actin fibers (yellow arrows) extend to the cortical bone matrix, establishing a network throughout the bone matrix in WT bone. This network is not as extensive in mutant bone. Bars: (A and B) 20 um; (C and D) 10 um.

Copyright

This image is from Izu Y, J Cell Biol 2011 Jun 13;193(6):1115-30, and is displayed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License. J:174217

Associated Alleles

Symbol	Name
Col12a1^tm1Debi	collagen, type XII, alpha 1; targeted mutation 1, David E Birk

Associated Genotypes

Allelic Composition	Genetic Background
Col12a1^tm1Debi/Col12a1^tm1Debi	involves: 129 * C57BL/6