The pineapple MADS-box gene family and the evolution of early monocot flower

Abstract

Unlike the flower of the model monocot rice, which has diverged greatly from the ancestral monocot flower, the pineapple (Ananas comosus) flower is more typical of monocot flowers. Here, we identified 43 pineapple genes containing MADS-box domains, including 11 type I and 32 type II genes. RNA-seq expression data generated from five pineapple floral organs (sepals, petals, stamens, pistils, and ovules) and quantitative real-time PCR revealed tissue-specific expression patterns for some genes. We found that AcAGL6 and AcFUL1 were mainly expressed in sepals and petals, suggesting their involvement in the regulation of these floral organs. A pineapple ‘ABCDE’ model was proposed based on the phylogenetic analysis and expression patterns of MADS-box genes. Unlike rice and orchid with frequent species-specific gene duplication and subsequent expression divergence, the composition and expression of the ABCDE genes were conserved in pineapple. We also found that AcSEP1/3, AcAG, AcAGL11a/b/c, and AcFUL1 were highly expressed at different stages of fruit development and have similar expression profiles, implicating these genes’ role in fruit development and ripening processes. We propose that the pineapple flower can be used as a model for studying the ancestral form of monocot flowers to investigate their development and evolutionary history.

Minimal number of morphoagronomic characters required for the identification of pineapple (Ananas comosus) cultivars in peatlands of Riau, Indonesia

“…These traits controlled by major genes include the distribution of spines and flower color. Both characters are controlled by 1-2 genes (Hu et al 2021). Furthermore, Burhooa & Ranghoo-Sanmukhiya (2012) reported that leaf shape and fruit shape could clearly distinguish pineapples.…”

A global alfalfa diversity panel reveals genomic selection signatures in Chinese varieties and genomic associations with root development

“…These characteristics may allow alfalfa to adapt to diverse environments. In different geographic alfalfa groups (corresponding to the top 1% tail of Tajima's D values), we found several phenology-related genes (Figure 3C), including Msa0206730 (MsKNOX1, MsG0280008879 in Zhongmu No.1 genome), Msa0876740 (MsMADS20-1, MsG0680030394), Msa0876740 (MsMADS20-2, MsG0680030395) and Msa0868930 (MsMYB, MsG0680030409) which have been shown to be associated with plant growth, development, and flowering (Nishii et al, 2017;Hu et al, 2021;Naik et al, 2021;Pelayo et al, 2021).…”

A short review on identification of ABCDE genes in monocot plants

“…Recent studies in conserved ABCDE MADS-box genes in pineapple have been identified and are homologous to ABCDE floral development model in Arabidopsis sp., rice, and Antirrhinum sp.. Two A-class genes were identified from pineapple, AcFUL1 and AcFUL2. AcFUL1 have similarity with FUL-like I rice genes such as OsMADS15 and OsMADS14, and AcFUL2 is similar to FUL-like II rice genes such as OsMADS18 and OsMADS20 [12]. Volume The MADS-box gene characterization from oil palm identified 12 genes, of them EgSQUA1, EgSQUA2, and EgSQUA3 which are SQUAMOSA subfamily of Class A genes.…”

“…Although not all MADS-box genes are homeotic, they can act as meristem identity genes. ABC model was a new approach towards flower initiation proposed in 1991 to make clear the ability of homeotic genes in the organ identity of a flower suggests that the organ identity in each flower whorls is determined by a unique companies activity of three organ identity genes [12]. The ABC model was subsequently expanded to the ABCDE model [3][4][5][13][14][15].…”