Molecular cloning, phylogenetic analysis, and expression profiling of endoplasmic reticulum molecular chaperone BiP genes from bread wheat (Triticum aestivum L.)

Abstract

BackgroundThe endoplasmic reticulum chaperone binding protein (BiP) is an important functional protein, which is involved in protein synthesis, folding assembly, and secretion. In order to study the role of BiP in the process of wheat seed development, we cloned three BiP homologous cDNA sequences in bread wheat (Triticum aestivum), completed by rapid amplification of cDNA ends (RACE), and examined the expression of wheat BiP in wheat tissues, particularly the relationship between BiP expression and the subunit types of HMW-GS using near-isogenic lines (NILs) of HMW-GS silencing, and under abiotic stress.ResultsSequence analysis demonstrated that all BiPs contained three highly conserved domains present in plants, animals, and microorganisms, indicating their evolutionary conservation among different biological species. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) revealed that TaBiP (Triticum aestivum BiP) expression was not organ-specific, but was predominantly localized to seed endosperm. Furthermore, immunolocalization confirmed that TaBiP was primarily located within the protein bodies (PBs) in wheat endosperm. Three TaBiP genes exhibited significantly down-regulated expression following high molecular weight-glutenin subunit (HMW-GS) silencing. Drought stress induced significantly up-regulated expression of TaBiPs in wheat roots, leaves, and developing grains.ConclusionsThe high conservation of BiP sequences suggests that BiP plays the same role, or has common mechanisms, in the folding and assembly of nascent polypeptides and protein synthesis across species. The expression of TaBiPs in different wheat tissue and under abiotic stress indicated that TaBiP is most abundant in tissues with high secretory activity and with high proportions of cells undergoing division, and that the expression level of BiP is associated with the subunit types of HMW-GS and synthesis. The expression of TaBiPs is developmentally regulated during seed development and early seedling growth, and under various abiotic stresses.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-014-0260-0) contains supplementary material, which is available to authorized users.

Wheat grain protein accumulation and polymerization mechanisms driven by nitrogen fertilization

“…BIP2 is a protein known for its role in preventing protein misfolding, facilitating protein folding and assembling protein bodies for subsequent transport from the endoplasmic reticulum to the cytoplasm (She et al ., ; Zhu et al ., ). We observed a slight upregulation of BIP2 at 21 and 28 DPA under high nitrogen availability.…”

Genome-wide identification and characterization ofSolanum tuberosum BiPgenes reveals the role of the promoter architecture in BiP gene diversity

“…Therefore, the characterization of BiPs is a crucial contribution to the understanding of cellular, tissuespecific and developmentally related responses to ER stress. The BiP gene family has been investigated in several plant species, including Arabidopsis, rice, wheat, pepper and citrus 36,37,[41][42][43][44] . In addition, there are several historic and recent studies using transgenic lines overexpressing various BiPs to characterize their roles in plant tolerance to adverse environmental conditions or demonstrating some evidence for tissue specific regulation 6,15,32,36,43,45 .…”

“…The UPR-related elements were previously identified in the AtBiP promoters 36,37 . Here we identify the UPR element II (UPRE-II), UPRE-III, ER stress-response element I (ERSE-I) and…”

“…The amino acid and nucleotide sequences for BiP homologs in N. benthamiana, N. tabacum, and S. lycopersicum were reported in Liebrand et al, (2012Liebrand et al, ( , 2014 and Jing et al (2016) however the gene accessions were not reported 37,86,33 . For S. lycopersicum, we identified the same sequences in the SolGen database and we report the Locus and Transcript IDs.…”

Synthesis and accumulation of glutenin subunits during grain development in bread wheat as revealed by reversed-phase ultra-performance liquid chromatography (RP-UPLC)

“…Hurkman et al (2009) also found that PDI had very abundant content at early stages of grain development. More recently, Zhu et al (2014b) has demonstrated that TaBip has the highest expression level at 14 DPA. The high expression of those molecular chaperones along with the rapid accumulation rate of 1Dx5 + 1Dy10 subunits at early grain development stages could facilitate the folding of gluten proteins and help to bring about the formation of more regular gluten polymers, which might result in superior gluten quality.…”