Col11a1a Expression Is Required for Zebrafish Development

Abstract

The autosomal dominant chondrodystrophies, the Stickler type 2 and Marshall syndromes, are characterized by facial abnormalities, vision deficits, hearing loss, and articular joint issues resulting from mutations in COL11A1. Zebrafish carry two copies of the Col11a1 gene, designated Col11a1a and Col11a1b. Col11a1a is located on zebrafish chromosome 24 and Col11a1b is located on zebrafish chromosome 2. Expression patterns are distinct for Col11a1a and Col11a1b and Col11a1a is most similar to COL11A1 that is responsible for human autosomal chondrodystrophies and the gene responsible for changes in the chondrodystrophic mouse model cho/cho. We investigated the function of Col11a1a in craniofacial and axial skeletal development in zebrafish using a knockdown approach. Knockdown revealed abnormalities in Meckel’s cartilage, the otoliths, and overall body length. Similar phenotypes were observed using a CRISPR/Cas9 gene-editing approach, although the CRISPR/Cas9 effect was more severe compared to the transient effect of the antisense morpholino oligonucleotide treatment. The results of this study provide evidence that the zebrafish gene for Col11a1a is required for normal development and has similar functions to the mammalian COL11A1 gene. Due to its transparency, external fertilization, the Col11a1a knockdown, and knockout zebrafish model systems can, therefore, contribute to filling the gap in knowledge about early events during vertebrate skeletal development that are not as tenable in mammalian model systems and help us understand Col11a1-related early developmental events.

The Shape of the Jaw—Zebrafish Col11a1a Regulates Meckel’s Cartilage Morphogenesis and Mineralization

“…This timepoint was chosen because at this time, most of the cartilage elements have developed and can be stained with Alcian blue to detect the cartilaginous ventral pharyngeal skeleton. Col11a1a antisense morpholino oligonucleotide (AMO) induced a curved body shape overall, making morphants distinguishable from stage-matched controls, consistent with our previous findings ( Figure 1 A,B) [ 25 ]. The midface had a flattened appearance and the jaw size was reduced ( Figure 1 C,D).…”

“… Col11a1a knockdown caused a curved body plan and reduced jaw size in zebrafish. Injection of a col11a1a targeting AMO induced a curvature of the body axis, while embryos injected with control AMO developed a straight body axis, ( A , B ); (( A , B ) reprinted under the terms and conditions of the Creative Commons Attribution (CC BY) license ( ; Accessed on 15 July 2022) [ 25 ]. Normal face and jaw protrusion were present in the control zebrafish ( C ).…”

“…This study seeks to elucidate the impact of zebrafish col11a1a on Meckel’s cartilage morphogenesis and cellular organization during jaw development. In our previous studies, zebrafish col11a1a expression was located within the developing jaw using in situ hybridization [ 24 , 25 ]. Using a recently developed antibody, we also identified the zebrafish Col11a1a protein within the developing jaw [ 26 ].…”