High impact information on EKI1

• The zinc-mediated regulation of EKI1 expression was attenuated in the zap1Delta mutant defective in the zinc-regulated transcription factor Zap1p [1].
• Ethanolamine kinase catalyzes the committed step in the synthesis of phosphatidylethanolamine via the CDP-ethanolamine branch of the Kennedy pathway [1].
• The beta-galactosidase activity driven by the P(EKI1)-lacZ reporter gene was elevated in zinc-depleted cells, indicating that the increase in ethanolamine kinase activity was attributed to a transcriptional mechanism [1].
• Moreover, mutational analysis showed that the UAS(INO) element in the EKI1 promoter was required for the inositol-mediated regulation [2].
• Using a cki1Delta eki1Delta mutant defective in choline kinase and ethanolamine kinase, we examined the consequences of a block in the Kennedy pathway on the regulation of phosphatidylcholine synthesis by the CDP-diacylglycerol pathway [3].

Biological context of EKI1

• A multicopy plasmid containing the EKI1 gene directed the overexpression of ethanolamine kinase activity in wild-type, eki1Delta mutant, cki1Delta mutant, and eki1Delta cki1Delta double mutant cells [4].
• The heterologous expression of the S. cerevisiae EKI1 gene in Sf-9 insect cells resulted in a 165,500-fold overexpression of ethanolamine kinase activity relative to control insect cells [4].
• Transcription of the EKI1 gene was monitored by following the expression of beta-galactosidase activity driven by a P(EKI1)-lacZ reporter gene [2].
• We identify a human cDNA encoding an ethanolamine-specific kinase EKI1 and the structure of the EKI1 gene located on chromosome 12 [5].

Anatomical context of EKI1

• EKI1 overexpression in COS-7 cells results in a 170-fold increase in ethanolamine kinase-specific activity and accelerates the rate of [3H]ethanolamine incorporation into PtdEtn as a function of the ethanolamine concentration in the culture medium [5].

Associations of EKI1 with chemical compounds

• Whereas the EKI1 gene product was primarily responsible for phosphatidylethanolamine synthesis via the CDP-ethanolamine pathway, the CKI1 gene product was primarily responsible for phosphatidylcholine synthesis via the CDP-choline pathway [4].
• Ethanolamine kinase (ATP:ethanolamine O-phosphotransferase, EC 2.7.1. 82) catalyzes the committed step of phosphatidylethanolamine synthesis via the CDP-ethanolamine pathway [4].
• EKI1 has negligible choline kinase activity in vitro and does not influence phosphatidylcholine biosynthesis [5].

Other interactions of EKI1

• The EKI1 gene product also exhibited choline kinase activity [4].
• Direct interactions between Zap1p and putative zinc-responsive elements in the EKI1 promoter were demonstrated by electrophoretic mobility shift assays [1].

References