Genome-wide identification of theMADS-boxtranscription factor family in pear (Pyrus bretschneideri) reveals evolution and functional divergence

Abstract

MADS-box transcription factors play significant roles in plant developmental processes such as floral organ conformation, flowering time, and fruit development. Pear (Pyrus), as the third-most crucial temperate fruit crop, has been fully sequenced. However, there is limited information about the MADS family and its functional divergence in pear. In this study, a total of 95 MADS-box genes were identified in the pear genome, and classified into two types by phylogenetic analysis. Type I MADS-box genes were divided into three subfamilies and type II genes into 14 subfamilies. Synteny analysis suggested that whole-genome duplications have played key roles in the expansion of the MADS family, followed by rearrangement events. Purifying selection was the primary force driving MADS-box gene evolution in pear, and one gene pairs presented three codon sites under positive selection. Full-scale expression information for PbrMADS genes in vegetative and reproductive organs was provided and proved by transcriptional and reverse transcription PCR analysis. Furthermore, the PbrMADS11(12) gene, together with partners PbMYB10 and PbbHLH3 was confirmed to activate the promoters of the structural genes in anthocyanin pathway of red pear through dual luciferase assay. In addition, the PbrMADS11 and PbrMADS12 were deduced involving in the regulation of anthocyanin synthesis response to light and temperature changes. These results provide a solid foundation for future functional analysis of PbrMADS genes in different biological processes, especially of pigmentation in pear.

Genome‐wide analysis of MADS‐box family genes during flower development in lettuce

“…Thus, these two gene types may be regulated by different mechanisms, with the more complex mechanisms controlling type II genes. A similar phenomenon was observed in A. thaliana , pear, and cucumber (Hu & Liu, ; Parenicova et al, ; Wang et al, ). Additionally, most type I genes were highly expressed in a single stage, whereas type II genes were usually expressed in successive developmental periods.…”

A Cucumber AGAMOUS-LIKE 15 (AGL15) MADS-Box Gene Mediates Abnormal Leaf Morphology in Arabidopsis

“…As shown in Figure 5, the expression of CsMADS26 was detected in the six tested tissues, with the highest levels in male flower and female flower, followed by fruit and leaf, and much lower levels in stem and root. CsMADS26 is mainly expressed in reproductive organs, which is in agreement with the profiles of other AGL15 subfamily genes in various plants, including Prunus mume (PmMADS30) [33], Vitis vinifera (VvMADS20 and VvMADS25) [34], P. bretschneideri (PbrMADS34 and PbrMADS37) [9], Z. jujuba (ZjMADS42 and ZjMADS45) [10], G. hirsutum (GhAGL15-3) [2], D. caryophyllus (DcaMADS22 and DcaMADS23) [12], and M. notabilis (MnMADS6) [7], indicating its important function in the development of reproductive organs. In addition, its expression was also observed in leaf, indicating that CsMADS26 might play a role in leaf development.…”

“…As a result, CsMADS26 contains 55.86% alpha helices, 12.61% extended strands, 4.50% beta turns, and 27.03% random coils, respectively ( Figure 2). Previous reports have suggested that the K domain is mainly responsible for dimerization [2,9]. However, CsMADS26 possesses a large number of alpha helices in its K domain, suggesting that CsMADS26 may have a particular function in facilitating the dimerization of MADS-box proteins.…”

“…AGL15 and AGAMOUS-LIKE18 (AGL18) constitute the AGL15 subfamily, and many AGL15 subfamily members were recently identified by genome-wide approaches in many plant species, including Cucumis melo [6], Pyrus bretschneideri [9], Ziziphus jujuba [10], Gossypium hirsutum [2,11], Dianthus caryophyllus [12], Morus notabilis [7], and Hevea brasiliensis [13]. These studies showed that the expression of AGL15 subfamily members is primarily detected in floral organs, implying their important roles in the development of floral organs.…”

The genetic architecture of fruit colour in strawberry (Fragaria × ananassa) uncovers the predominant contribution of theF. vescasubgenome to anthocyanins and reveals underlying genetic variations

“…The involvement of MADS-box genes in anthocyanin accumulation have been reported in different species including Arabidopsis (Nesi et al 2002) and other Rosaceae fruit species such as bilberry (Jaakola et al 2010) and pear (Wang et al 2017). Among the four MADS box candidates expressed in fruit cortex, two of them ( gene26119 , gene06301 ) that are expressed at late stages of fruit development (Hawkins et al 2017) show a pattern of expression opposite to that of ANR, which makes them potential candidates for regulating ANR in strawberry fruit.…”