High impact information on SUR2

• The TRAP100-deficient TRAP/Mediator complex also lacks TRAP95 and TRAP150 beta/SUR2, which together with TRAP100 may form a submodule, and contains a reduced amount of SRB10/CDK8 [1].
• Gene dosage experiments using the sphingolipid long chain sphingoid base (LCB) hydroxylase gene, SUR2, suggest that erg26-1 cells may accumulate LCB, thus placing one point of sterol regulation of sphingolipid synthesis possibly at the level of ceramide metabolism [2].
• These results show that the SYR2 gene is required for the 4-hydroxylation reaction of sphingolipid long chain bases, that this hydroxylation is not essential for growth, and that the 4-hydroxyl group of sphingolipids is necessary for syringomycin E action on yeast [3].
• The Saccharomyces cerevisiae gene SYR2, necessary for growth inhibition by the cyclic lipodepsipeptide syringomycin E, is shown to be required for 4-hydroxylation of long chain bases in sphingolipid biosynthesis [3].
• Mutants defective in both YSR2 and SUR2, which accumulated dihydrosphingosine 1-phosphate only, grew poorly [4].

Biological context of SUR2

• Neither SCS7 nor SUR2 are essential for growth, and lack of the Scs7p- or Sur2p-dependent hydroxylation does not prevent the synthesis of mannosyldiinositolphosphorylceramide, the mature sphingolipid found in yeast [5].
• A syringomycin-E resistance phenotype of a S. cerevisiae sur2-null mutant was complemented by expression of the cloned P. ciferrii SUR2 gene [6].
• We isolated the SUR2 gene from Pichia ciferrii using nucleotide sequence homology to S. cerevisiae SUR2 to study hydroxylation of sphinganine in the sphingoid base overproducing yeast P. ciferrii [6].
• Gene disruption or overexpression of SYR2 did not affect cell viability or ergosterol levels, but did influence cellular phospholipid levels [7].
• The roles of putative active site residues of the Saccharomyces cerevisiae sphingolipid C-4 long chain base hydroxylase (Sur2p) were investigated by site-directed mutagenesis [8].

Anatomical context of SUR2

• SYR2 was cloned, sequenced, and shown to encode a 349 amino acid protein located in the endoplasmic reticulum [7].

Associations of SUR2 with chemical compounds

• SUR2 catalyzes conversion of dihydrosphingosine to phytosphingosine [4].

Other interactions of SUR2

• Ten mutants were obtained, ranged amongst four complementation groups, named SUR1, SUR2, SUR3 and SUR4 [9].
• Two other genes involved in sphingolipid biosynthesis (LCB2 and SUR2) were found to contain PDREs in their promoters and to be induced by the Pdr pathway [10].
• Both predicted proteins consist of 258 amino acid residues (77% identity) which show sequence similarity to di-iron-binding enzymes, such as Sur2p and Erg3p from yeast, involved in oxygen-dependent lipid modifications [11].

References