Expression of chondroitin/dermatan sulfate glycosyltransferases during early zebrafish development

Abstract

Background: Chondroitin/dermatan sulfate (CS/DS) proteoglycans present in the extracellular matrix have important structural and regulatory functions. Results: Six human genes have previously been shown to catalyze CS/DS polymerization. Here we show that one of these genes, chpf, is represented by two copies in the zebrafish genome, chpfa and chpfb, while the other five human CS/DS glycosyltransferases csgalnact1, csgalnact2, chpf2, chsy1, and chsy3 all have single zebrafish orthologues. The putative zebrafish CS/DS glycosyltransferases are spatially and temporally expressed. Interestingly, overlapping expression of multiple glycosyltransferases coincides with high CS/DS deposition. Finally, whereas the relative levels of the related polysaccharide HS reach steady-state at around 2 days post fertilization, there is a continued relative increase of the CS amounts per larvae during the first 6 days of development, matching the increased cartilage formation. Conclusions: There are 7 CS/DS glycosyltransferases in zebrafish, which, based on homology, can be divided into the CSGALNACT, CHSY, and CHPF families. The overlap between intense CS/DS production and the expression of multiple CS/DS glycosyltransferases suggests that efficient CS/DS biosynthesis requires a combination of several glycosyltransferases. Developmental Dynamics 242:964-975, 2013. V C 2013 Wiley Periodicals, Inc.Key words: chondroitin sulfate; polymerase; CSGALNACT; CHSY; CHPF; zebrafish Key Findings:The zebrafish genes csgalnact1, csgalnact2, chsy1, chsy3, chpf2, chpfa, and chpfb are orthologues to the human genes that mediate CS/DS polymerization. Chordate CS/DS glycosyltransferases may be divided into the CSGALNACT, CHSY, and CHPF families. Sites of high CS/DS production in zebrafish embryos are characterized by the overlapping expression of multiple CS/DS producing glycosyltransferases. The content of CS/DS per fish is massively increased during zebrafish larval development whereas the heparan sulfate content gets stabilized around 48 hpf.

Spinal Deformity in Aged Zebrafish Is Accompanied by Degenerative Changes to Their Vertebrae that Resemble Osteoarthritis

“…HS expression is high in the first 24 hours of life (~50%), but decreases as a proportion of total GAG content thereafter; whereas CS and KS increase throughout life [53]. Our study indicates that KS, identified by mAb 5D4, is largely absent from the vertebral column, only occurring within the intervertebral tissue, where it is strongly expressed by vacuolated notochordal cells in 1 year samples.…”

The Morphogenesis of Cranial Sutures in Zebrafish

“…Specimens were embedded using the Microm EC350-2 tissue-embedding center. All tissue samples were sectioned at 5 μm using rotary microtome and stained with Hematoxylin and Eosin (H&E) [33] to evaluate morphological structures. Zeiss Axioplan2 Imaging Microscope equipped with an Axiocam HRc camera was used for imaging.…”

Chondroitin / Dermatan Sulfate Modification Enzymes in Zebrafish Development

“…However, if HS or CS will be synthesized also depends on other factors such as amino acid properties in close vicinity to the attachment serine residue [ 8 ] and sulfation of the link structure [ 9 ]. Elongation of CS/DS by repeating additions of GalNAc and GlcA is the result of a concerted action of CS/DS glycosyltransferases [ 5 , 6 , 10 ].…”

“…We have previously characterized CS/DS polymerization during zebrafish development [ 10 ] and in this study we systematically investigate the phylogeny and expression of all known CS/DS modification enzymes as well as the temporal variation of CS/DS structures. We conclude that CS/DS biosynthesis is a highly dynamic regulated process during vertebrate development.…”