Molecular cloning and characterization of a cassava translationally controlled tumor protein gene potentially related to salt stress response

Abstract

Cassava (Manihot esculenta Crantz) is one of the most important tropical crops showing tolerance to abiotic stress and adaptations to a wide range of environmental conditions. Here, we aimed to isolate and characterize the full-length cDNA and genomic sequences of a cassava translationally controlled tumor protein gene (MeTCTP), and evaluate its potential role in response to salt stress. The MeTCTP full-length cDNA sequence encodes for a deduced protein with 168 amino acid residues, with theoretical isoelectric point and molecular weight of 4.53 and 19 kDa, respectively, containing two putative signatures of TCTP family and one site for myristoylation. The MeTCTP genomic sequence includes four introns and five exons within a 1,643 bp coding region, and a 264 bp partial promoter sequence containing several putative cis-acting regulatory elements, among them, two putative GT-1 motifs, which may be related to response to sodium chloride (NaCl) and pathogen infection. Semi-quantitative RT-PCR assays showed that MeTCTP transcripts were higher in roots than leaves, and were significantly increased in detached leaves treated with NaCl. Furthermore, the recombinant MeTCTP conferred a protective function against salt stress in bacterial cells. We report for the first time the molecular cloning and characterization of a cassava TCTP with potential role in salt-stress response. Since salinity is one the most important abiotic factors affecting the production of crops worldwide, the MeTCTP gene could be a candidate gene for generation of salt tolerant crops.

Impacts of the overexpression of a tomato translationally controlled tumor protein (TCTP) in tobacco revealed by phenotypic and transcriptomic analysis

“…Supporting the idea that plant TCTPs present overlapping functions in plant growth and stress response, in addition to improved biomass production, the SlTCTP-OE lines also displayed better performance under abiotic stress conditions. Despite being first observed in bacterial cells (Santa Brígida et al 2014), here we show for the first time that the overexpression of a plant TCTP is able to reduce salt-stress sensitivity at the whole plant level. Similarly, SlTCTP overexpression improved plant performance under osmotic stress.…”

“…As their mammalian counterpart, plant TCTPs are frequently reported as microtubule-and Ca 2+ -binding proteins (Kim et al 2012;Hoepflinger et al 2013;Li et al 2013). Compelling evidences also indicate that plant TCTPs are regulated in response to a wide array of stimuli including low temperature (Li et al 2013), salt (Li et al 2013;Santa Brígida et al 2014), wounding (Li et al 2013), drought (Ghabooli et al 2013;Li et al 2013), induced programmed cell death (Chen et al 2014), mercury (Wang et al 2015), aluminum (Ermolayev et al 2003), hydrogen peroxide (Li et al 2013;Wang et al 2015) and infection by different pathogens (Alfenas-Zerbini et al 2009;Li et al 2013). TCTP expression is also influenced by different phytohormones, i.e., methyl jasmonate (Li et al 2013), abscisic acid (ABA) (Kim et al 2012;Wang et al 2015) and ethylene (Tao et al 2015).…”

<b>Salinity reduces carbon assimilation and the harvest index of cassava plants (<i>Manihot esculenta</i> Crantz)

“…In research conducted by Hawker and Smith (1982), salinity seriously affected cassava growth; because of this, they considered it a moderately salt sensitive species. Recently, studies have been exploring salinity effects with a focus on the proteome and genome analysis of cassava (Costa et al, 2011;An et al, 2014;Santa Brígida et al, 2014).…”

Mild osmotic stress in intertidal gastropods Littorina saxatilis and Littorina obtusata (Mollusca: Caenogastropoda): a proteomic analysis

“…TCTP is also an important participant of the TOR-pathway, a nutrition sensor and growth regulator in different organisms (Deprost et al, 2007;Brioudes et al, 2010). Its regulation was detected during salinity stress in plants and bacteria (Vincent et al, 2007;Santa Brígida et al, 2014). TCTP proved to be down-regulated during mild salinity stress in both Littorina species.…”