Genome-wide identification and characterization of the metal tolerance protein (MTP) family in grape (Vitis vinifera L.)

Abstract

Metal tolerance proteins (MTPs) play an important role in the transport of metals at the cellular, tissue and whole plant levels. In the present study, 11 MTP genes were identified and these clustered in three major sub-families Fe/Zn-MTP, Zn-MTP, and Mn-MTP, and seven groups, which are similar to the grouping of MTP genes in both Arabidopsis and rice. Vitis vinifera metal tolerance proteins (VvMTP) ranged from 366 to 1092 amino acids, were predicted to be located in the cell vacuole, and had four to six putative TMDs, except for VvtMTP12 and VvMTP1. The VvMTPs had putative cation diffusion facilitator (CDF) domains and the putative Mn-MTPs also had zinc transporter dimerization domains (ZD-domains). V. vinifera Mn-MTPs had gene structures and motif distributions similar to those of the Fe/Zn-MTP and Zn-MTP sub-families. The upstream regions of VvMTP genes had variable frequencies of cis-regulatory elements that could indicate regulation at different developmental stages and/or differential regulation in response to stress. Comparison of the VvMTP coding sequences with known miRNAs found in various plant species indicated the presence of 13 putative miRNAs, with 7 of these associated with VvMTPs. Temporal and spatial expression profiling indicates a potential role for VvMTP genes during growth and development in grape plants, as well as the involvement of these genes in plant responses to environmental stress, especially osmotic stress. The data generated from this study provides a basis for further investigation of the roles of MTP genes in grapes.

Genome-Wide Identification of Metal Tolerance Protein Genes in Populus trichocarpa and Their Roles in Response to Various Heavy Metal Stresses

“…Compared with that of previous report, three new MTP genesn were found in P. trichocarpa [20]. The number of MTPs in P. trichocarpa was only second to N. tabacum among the plant species in which the MTPs have been identified [5,8,[22][23][24][25][26][27][28]. However, despite the large number of PtrMTPs, the homolog of AtMTP2 in P. trichocarpa was not detected.…”

Genome-Wide Identification, Structure Characterization, Expression Pattern Profiling, and Substrate Specificity of the Metal Tolerance Protein Family in Canavalia rosea (Sw.) DC

“…Similarly, there were at least 20 TaMTP sequences in modern wheat Triticum aestivum (hexaploid, AABBDD) [ 56 ]. However, in sweet orange ( Citrus sinensis ) and grape ( Vitis vinifera ) genomes, there were 12 and 11 members of CitMTPs and VvMTPs, respectively [ 14 , 57 ]. Additionally, there were 13 CsMTPs identified from Mn hyperaccumulator tea plants ( Camellia sinensis ) [ 53 ].…”

“…Although there is limited experimental evidence that plant MTPs are involved in high salinity and drought tolerance, some previous reports indicated that MTPs might be related to some adaptations to abiotic stressors, except HMs. The expression of Arabidopsis MTP s was determined under various abiotic stressors in both root and shoot tissues by RNA-seq, and AtMTP9 showed the highest level of expression in response to salt and high osmotic stress [ 57 ]. A cation diffusion facilitator gene from soybean, GmCDF1 ( GmMTP12 ), negatively regulates salt tolerance by regulating K + -Na + homeostasis [ 60 ].…”

Dose-Dependent Physiological and Transcriptomic Responses of Lettuce (Lactuca sativa L.) to Copper Oxide Nanoparticles—Insights into the Phytotoxicity Mechanisms

“…Metal tolerance proteins (MTPs) are crucial for metal transport at the cellular, tissue, and whole plant levels [81]. Fu et al (2017) observed that several CitMTP genes are significantly upregulated under Cu toxicity [82].…”