Col11a1a Expression Is Required for Zebrafish Development.

Makenna J Hardy,Jonathon C Reeck,Ming Fang,Julia Thom Oxford,Jason S Adams

doi:10.3390/jdb8030016

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.

Highlights

The molecular mechanisms directing developmental patterning and gene expression at early stages in vertebrate development are conserved in many respects between zebrafish and humans, with cartilage forming the majority of the vertebrate embryonic skeleton in early development, relying on mesenchymal cell proliferation and condensation [1,2]
We identified zebrafish orthologues of the minor fibrillar collagen genes and analyzed the exons included within the specific splice forms
The Danio rerio Col11a1a gene is located on chromosome 24 and the Col11a1b gene is located on chromosome 2

Summary

Introduction

The molecular mechanisms directing developmental patterning and gene expression at early stages in vertebrate development are conserved in many respects between zebrafish and humans, with cartilage forming the majority of the vertebrate embryonic skeleton in early development, relying on mesenchymal cell proliferation and condensation [1,2]. Chondroprogenitor proliferation and terminal differentiation lead to the formation of precisely sized and shaped skeletal elements [3]. 2020, 8, 16 defects during this process can lead to chondrodystrophies that may include abnormal bone formation, joint dysfunction, and early-onset osteoarthritis [4] Biol. 2020, 8, 16 defects during this process can lead to chondrodystrophies that may include abnormal bone formation, joint dysfunction, and early-onset osteoarthritis [4]

Methods

Results

Conclusion