Isopentenyl pyrophosphate isomerases from Melaleuca alternifolia (Cheel) and their role in isoprenoid biosynthesis
JOURNAL OF HORTICULTURAL SCIENCE & BIOTECHNOLOGY
Authors: Shelton, DA; Leach, DN; Henry, RJ
Abstract
Two cDNA clones, idi1 and idi2, representing different isoforms of isopentenyl pyrophosphate isomerase (IPP isomerase) were isolated from Melaleuca alternifolia (Cheel) by functional complementation of carotenoid biosynthesis in E. coli. Excluding the putative transit peptide region, the isoforms share 89.5% predicted protein sequence identity. The high level of conservation between the isoforms indicates that these genes may share a common ancestral origin and supports the proposition that cytosolic and plastid targeted IPP isomerase may be differentially translated from a single gene. This study supports recent evidence suggesting that isopentenyl pyrophosphate and dimethylallylic pyrophosphate are both immediate products of the deoxyxylulose pathway and that IPP isomerase may have a more central role in the biosynthesis of carotenoids than in the biosynthesis of monoterpenes.
Development of cytotoxicity-sensitive human cells using overexpression of long non-coding RNAs
JOURNAL OF BIOSCIENCE AND BIOENGINEERING
Authors: Tani, Hidenori; Torimura, Masaki
Abstract
Biosensors using live cells are analytical devices that have the advantage of being highly sensitive for their targets. Although attention has primarily focused on reporter gene assays using functional promoters, cell viability assays are still efficient. We focus on long non-coding RNAs (IncRNAs) that are involved in the molecular mechanisms associated with responses to cellular stresses as a new biological material. Here we have developed human live cells transfected with IncRNAs that can be used as an intelligent sensor of cytotoxicity for a broad range of environmental stresses. We identified three IncRNAs (GAS5, IDI2-AS1, and SNHG15) that responded to cycloheximide in HEK293 cells. Overexpression of these IncRNAs sensitized human cells to cell death in response to various stresses (cycloheximide, ultraviolet irradiation, mercury II chloride, or hydrogen peroxide). In particular, dual IncRNA (GAS5 plus ID12-AS1, or GASS plus SNHG15) overexpression sensitized cells to cell death by more cellular stresses. We propose a method for highly sensitive biosensors using overexpression of IncRNAs that can potentially measure the cytotoxicity signals of various environmental stresses. (C) 2014, The Society for Biotechnology, Japan. All rights reserved.