Genome-wide characterization and expression analysis of α-amylase and β-amylase genes underlying drought tolerance in cassava

Abstract

Background Starch hydrolysates are energy sources for plant growth and development, regulate osmotic pressure and transmit signals in response to both biological and abiotic stresses. The α-amylase (AMY) and the β-amylase (BAM) are important enzymes that catalyze the hydrolysis of plant starch. Cassava (Manihot esculenta Crantz) is treated as one of the most drought-tolerant crops. However, the mechanisms of how AMY and BAM respond to drought in cassava are still unknown. Results Six MeAMY genes and ten MeBAM genes were identified and characterized in the cassava genome. Both MeAMY and MeBAM gene families contain four genes with alternative splicing. Tandem and fragment replications play important roles in the amplification of MeAMY and MeBAM genes. Both MeBAM5 and MeBAM10 have a BZR1/BES1 domain at the N-terminus, which may have transcription factor functions. The promoter regions of MeAMY and MeBAM genes contain a large number of cis-acting elements related to abiotic stress. MeAMY1, MeAMY2, MeAMY5, and MeBAM3 are proven as critical genes in response to drought stress according to their expression patterns under drought. The starch content, soluble sugar content, and amylase activity were significantly altered in cassava under different levels of drought stress. Conclusions These results provide fundamental knowledge for not only further exploring the starch metabolism functions of cassava under drought stress but also offering new perspectives for understanding the mechanism of how cassava survives and develops under drought.

Genome-wide identification of JAZ gene family members in autotetraploid cultivated alfalfa (Medicago sativa subsp. sativa) and expression analysis under salt stress

“…The results showed that there were more homologous gene pairs between alfalfa and M. truncatula than between A. thaliana and O. sativa , suggesting that the genetic background of autotetraploid alfalfa is more similar to that of M. truncatula . A similar phenomenon has been found in cassava [ 65 ]. In addition, we found that MsJAZ8 and MsJAZ17 were collinear in all the plants, indicating that these genes played a vital role in the evolution of JAZ genes.…”

Genome-Wide Identification, Characterization, and Expression Analysis of Four Subgroup Members of the GH13 Family in Wheat (Triticum aestivum L.)

“…In rice, the structure of α-amylase varies considerably, with some members containing extraordinarily long intron regions, others with significantly fewer exons than average, and even some with 5′ untranslated region (5′ UTR) lengths exceeding that of the promoter [ 53 ]. Yang et al [ 54 ], on the other hand, presented very interesting results in which they categorized the cassava α-amylase family genes into three clusters, each of which is internally structurally conserved. This may indicate that α-amylase conservation in wheat is rare.…”

Genome-Wide Identification and Expression Profiling of the α-Amylase (AMY) Gene Family in Potato

“…In addition, the StAMY proteins exhibited varied conserved motif compositions, likely due to functional differentiation of the StAMY family during evolution. Alternative splicing can result in a polymorphic protein structure, as well as functional and transcriptional differentiation [ 47 ]. High sequence similarity and close evolutionary relationships were observed between StAMY2 and StAMY3 , StAMY5 , StAMY6 , and StAMY7 ; StAMY8 and StAMY9 , StAMY11 , StAMY12 , and StAMY13 ; and StAMY14 and StAMY15 , StAMY18, and StAMY19 .…”