The sulfotransferase XB5850668.L is required to apportion embryonic ectodermal domains

Area of Science:

• Developmental biology
• Molecular biology
• Biochemistry

Background:

• Sulfotransferase superfamily (SULT) enzymes modulate diverse biological molecules but their roles in embryonic development are not well understood.
• Six1, a key developmental regulator, was found to up-regulate LOC100037047, encoding the uncharacterized sulfotransferase XB5850668.L.

Purpose of the Study:

• To investigate the function of the uncharacterized sulfotransferase XB5850668.L in embryonic ectoderm patterning.
• To determine the role of XB5850668.L in processes regulated by the developmental gene Six1.

Main Methods:

• Loss- and gain-of-function assays were employed to study XB5850668.L.
• Gene expression domains for neural plate, neural crest, cranial placode, and otic vesicles were analyzed.
• Mutagenesis of the sulfotransferase catalytic domain was performed to assess the role of enzymatic activity.

Main Results:

• Knockdown of XB5850668.L led to reduced expression of epidermal, neural crest, cranial placode, and otic vesicle genes, with concurrent neural plate expansion.
• Overexpression of XB5850668.L had minor effects, occasionally expanding neural plate and neural crest domains while reducing placode and otic vesicle domains.
• Mutating key catalytic residues of XB5850668.L diminished the effects observed with wild-type protein overexpression.

Conclusions:

• XB5850668.L, a member of the SULT2 family, is crucial for embryonic ectoderm patterning.
• The observed effects of XB5850668.L on development are, in part, dependent on its sulfotransferase enzymatic activity.