Dynamic expression patterns of 6‐O endosulfatases during zebrafish development suggest a subfunctionalisation event for sulf2

Abstract

The 6-O-endosulfatase enzymes (Sulfs) edit the final sulfation pattern and function of heparan sulfate (HS) by removal of 6-O-sulfate groups from the chain. To date, two mammalian sulf genes have been identified that regulate many signalling pathways during embryonic development. In zebrafish a sulf1 ortholog and duplicate copies of the mammalian sulf2 gene, sulf2a and sulf2, have been identified, which contain conserved motifs characteristic of vertebrate sulf genes. Zebrafish sulf1 and sulf2a are broadly expressed in the central nervous system (CNS) and non-neuronal tissue including heart, somite boundaries, olfactory system, and otic vesicle, whereas sulf2 expression is almost entirely restricted to the CNS. The duplicate copies of sulf2 have distinct expression patterns, which together mirror that of mouse sulf2, suggesting duplication in the teleost lineage has been followed by subfunctionalisation, whereby both genes need to be preserved by selection to ensure the ancestral gene's expression profile and function is maintained. Developmental Dynamics 239:3312-3323,

Dynamics of Sonic hedgehog signaling in the ventral spinal cord are controlled by intrinsic changes in source cells requiring Sulfatase 1

“…Whole-mount in situ hybridization (ISH) was performed as described previously (Macdonald et al, 1994) using the following RNA probes: sulf1 (Gorsi et al, 2010), nkx2.2a (Barth and Wilson, 1995), nkx2.9 (Guner and Karlstrom, 2007), olig2 (Park et al, 2002), plp/dm20 (Park et al, 2002), foxa2 (Strähle et al, 1993), shh (Krauss et al, 1993), arx (Miura et al, 1997), pax7a (Seo et al, 1998), ptc1 (Concordet et al, 1996), pax2a (Pfeffer et al, 1998), islet2a (Appel et al, 1995), tal2 (Pinheiro et al, 2004), sim1 (Serluca and Fishman, 2001) and mbpa (Brösamle and Halpern, 2002). After ISH, embryos were embedded in gelatine/albumin and 10-15 μm sections were cut using a vibratome (Leica VT1000s).…”

“…Before patterning rearrangement, Sulf1 is expressed in the ventral neural tube (Braquart-Varnier et al, 2004;Danesin et al, 2006;Gorsi et al, 2010;Meyers et al, 2013;Touahri et al, 2012), opening the possibility that it could also influence Shh signaling at stages of patterning establishment. We report that, in addition to its function in stimulating OPC induction, Sulf1 activity is crucial for generation of ventral neuronal subtypes in zebrafish.…”

Expression of the heparan sulfate 6‐O‐endosulfatases, Sulf1 and Sulf2, in the avian and mammalian inner ear suggests a role for sulfation during inner ear development

“…Sulf1 and Sulf2 are expressed in similar regions of the developing embryo in several model systems (Freeman et al, ; Winterbottom and Pownall, ; Gorsi et al, ; Guiral et al, ; Ratzka et al, ). Both Sulf1 and Sulf2 share substrate specificity, and as such are considered functionally redundant (Ai et al, ; Ratzka et al, ).…”

“…Sulfs were first identified in Quail, with the description of QSulf1 (Dhoot et al, 2001), and mouse with the identification of mSulf1 and mSulf2 (Morimoto-Tomita et al, 2002). Orthologues have since been identified in chick, human, rat, zebrafish, and amphibian (Ohto et al, 2002;Braquart-Varnier et al, 2004;Nagamine et al, 2005;Freeman et al, 2008;Gorsi et al, 2010). Modification of HSPG sulfation by the Sulfs has been shown to regulate Shh, Wnt, FGF, BMP, GDNF, and VEGF signaling during embryonic development (Dhoot et al, 2001;Ai et al, 2003Ai et al, , 2007Wang et al, 2004;Danesin et al, 2006;Freeman et al, 2008;Meyers et al, 2013;Gorsi et al, 2014).…”

Analyzing the Role of Heparan Sulfate Proteoglycans in Axon Guidance In Vivo in Zebrafish

“…Dackel ( dak ), Boxer ( box ), and Pinscher ( pin ) lack functional Ext2, Extl3, and Papst1 (a sulfate transporter), respectively, and can be compared to wild-type (WT) animals for testing the role of HS in axonal development [13, 14, 36–38]. The other HS-modifying enzymes, as well as SDC and GPC core proteins, have been cloned and can be tested for their functions in vivo during development [39–46]. In this chapter, we describe methods for (1) visualizing axon pathfinding directly in the embryo, and (2) down-regulating the expression of genes of interest to test HSPGs’ functions.…”