Comparative transcriptome analysis reveals the transcriptional alterations in heat-resistant and heat-sensitive sweet maize (Zea mays L.) varieties under heat stress

Abstract

BackgroundDespite the heat-related physiology and heat-shock proteins in maize have been extensively studied, little is known about the transcriptome profiling of how the maize varieties with different genotypes responding to high temperatures. Seedling mortality of Xiantian 5 (XT) is significantly lower than that of Zhefengtian (ZF) when exposed to high temperature (42 °C for 6 h) and followed by a recovery growth (25 °C for one week). Therefore, we performed a transcriptome analysis using the total RNA extracted from the leaves of XT and ZF that were previously subjected to heat stress at 42 °C for 0 h, 0.5 h, and 3 h, respectively.ResultsA total of 516 commonly up-regulated and 1,261 commonly down-regulated genes were identified among XT/ZF, XT0.5/ZF0.5 and XT3/ZF3 using transcriptome analysis. Gene Ontology classification of the 516 up-regulated genes showed that their encoded proteins were significantly assigned to 18 cellular components, and were classified into 9 functional categories, and were involved in 9 biological processes. Most of proteins encoded by up-regulated genes were localized in chloroplast and its structural components, and involved in multiple biological processes associated with photosynthesis, indicating that these chloroplast proteins play an important role in increasing heat tolerance in sweet maize. While the proteins encoded by 1,261 down-regulated genes were significantly assigned to 31 cellular components, and were classified into 3 functional categories, and were involved in 9 biological processes. Interestingly, these proteins were involved in a series of biological processes from gene expression to translation, suggesting that lowering these processes may contribute to improved heat resistance in sweet maize. The up-regulated genes were identified to be involved in 36 distinct metabolic pathways, of which the most significant ones was secondary metabolite biosynthetic pathway. While the down-regulated genes were identified to be involved in 23 distinct metabolic pathways, of which the most significant ones were found in ribosome. Quantitative real-time PCR analysis demonstrated that 5 genes involved in the biosynthesis of secondary metabolites and photosynthesis in XT have higher abundance than those in ZF, whereas 5 ribosome genes in XT showed lower abundance than those in ZF. In addition, heat-tolerant sweet maize may keep at lower growth level than heat-sensitive one through dowregulating expression of genes related to zeatin and brassinosteroid biosynthesis to better regulate heat stress responses.ConclusionsComparative transcriptomic profiling reveals transcriptional alterations in heat-resistant and heat-sensitive sweet maize varieties under heat stress, which provides a new insight into underlying molecular mechanism of maize in response to heat stress.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-017-0973-y) contains supplementary material, which is available to authorized users.

Comparative Transcriptome Analysis of the Heat Stress Response in Monochamus alternatus Hope (Coleoptera: Cerambycidae)

“…CYPs catalyzed a broad range of oxidative substances, including insecticides, plant secondary metabolites, and some oxidative substances induced by heat exposure (Daborn et al, 2007;Niu et al, 2011). In the present study, upregulation of CYPs in M. alternatus, similar to other organisms treated with heat stress, certified this role of CYPs Shi et al, 2017). In addition to CYPs, organisms produced ALDHs in response to a suite of environmental stresses that perturb metabolism, including salinity, dehydration, desiccation, and cold and heat shock (Kirch et al, 2004).…”

“…De novo transcriptome assembly has been widely applied to detect and identify differential genes under different experimental conditions (He et al, 2017;Liu et al, , 2018Chen et al, 2018), enabling researchers to understand the molecular mechanism of action from a transcriptomics perspective. Different expression gene (DEGs) profiling in this technique presents the advantages of precision, economy, and repeatability, and has been widely used in plants to explore genes related to heat resistance (Li et al, 2015;Yan et al, 2016;Shi et al, 2017), while in insects, comparative transcriptome analysis related to heat responses has been only applied in several species, including G. pyloalis, Cryptolaemus montrouzieri, and Bombyx mori (Wang et al, 2014;Zhang Y.H. et al, 2015;.…”

Metabolic pathways analysis and identification of heat response genes of pineapple [Ananas comosus (L.) Merr.] fruit affected by elevated postharvest temperature

“…This result suggested that EPT process was a stimulus process compared to an appropriate temperature. Similar results were reported on Populus euphratica Oliver (Chen et al, 2015), Chrysanthemum (Sun et al, 2015), rice (Wu et al, 2015) and sweet maize (Shi et al, 2017) when subjected to heat stress. A few DEGs were observed to be annotated to GO terms of aromatic compound biosynthetic process, aromatic amino acid family metabolic process and cellular aromatic compound metabolic process, betaglucosidase activity, glucosidase activity and malate dehydrogenase activity as well as KEGG pathways of starch and sucrose metabolism, biosynthesis of secondary metabolites, pentose and glucuronate interconversions, carotenoid biosynthesis, metabolic pathways and galactose metabolism which indicated that these genes involved in aroma production and sugar/ acid metabolism were differentially expressed in the EPT process.…”

Unraveling Field Crops Sensitivity to Heat Stress: Mechanisms, Approaches, and Future Prospects

“…Transcriptomic changes drive the physiological response to progressive drought stress and rehydration in tomato [236]. In a recent study, comparative transcriptome analysis revealed the transcriptional alterations in heat-resistant and heat-sensitive sweet maize (Zea mays L.) varieties under HS [237]. Chen and Li [238] found that DEGs were responsible for HS and protein folding in Brachypodium distachyon.…”