Structural elucidation of selenocysteine insertion machinery of microalgal selenoprotein T and its transcriptional analysis
RESHMA (R), KUMARI (S), ARUMUGAM (M)
microalgae; ER stress; SECIS element; selenocysteine insertion machinery; selenoproteins; whole genome sequence
Biotechnology and Applied Biochemistry
Essential trace element selenium in association with selenoproteins, which is found in almost all organisms except higher plants and fungi, is involved in various biological functions. Advancement in the field of whole genome sequencing and data analyzing bioinformatic tools led to the accumulation of genome information of organisms. However, selenoproteins are unique and it needs specialized genomics tool for its identification as well as characterization. In this study, the presence of selenoprotein T (SelT) fromScenedesmus quadricaudawas shown for the first time with experimental evidence and compared with SelT of marine microalgaeNannochloropsis oceanica. Along with SelT, all the associated machineries required to synthesize the selenoproteins were also identified. Also, the present study tried to explicate the evolutionary relatedness of SelT of these two organisms with other known bacteria and eukaryotes. Transcript level analysis inS. quadricaudaunder endoplasmic reticulum stress showed a 1.2 +/- 0.28-fold increase in SelT expression. Thus, it provided the first experimental evidence on SelT expression from microalgae.