A PLENA-like gene of peach is involved in carpel formation and subsequent transformation into a fleshy fruit

Abstract

MADS-box genes have been shown to play a role in the formation of fruits, both in Arabidopsis and in tomato. In peach, two C-class MADS-box genes have been isolated. Both of them are expressed during flower and mesocarp development. Here a detailed analysis of a gene that belongs to the PLENA subfamily of MADS-box genes is shown. The expression of this PLENA-like gene (PpPLENA) increases during fruit ripening, and its ectopic expression in tomato plants causes the transformation of sepals into carpel-like structures that become fleshy and ripen like real fruits. Interestingly, the transgenic berries constitutively expressing the PpPLENA gene show an accelerated ripening, as judged by the expression of genes that are important for tomato fruit ripening. It is suggested that PpPLENA might interfere with the endogenous activity of TAGL1, thereby activating the fruit ripening pathway earlier compared with wild-type tomato plants.

Effect of seed on ripening control components during avocado fruit development

“…The expression patterns may suggest that PaAG1 and PaAGL9 genes are not controlled by ethylene, similarly to SlMADS-RIN and MaMADS2 both of which are involved in fruit ripening, and their expression levels were elevated at the onset of ripening (Elitzur et al, 2010;Ito et al, 2008;Vrebalov et al, 2002). The expression of peach PLENA-like gene also increased during fruit ripening (Tadiello et al, 2009). It is possible that at least PaAG1, with its expression induced during development, is playing a role in fruit growth, while PaAGL9 and PaAG1 are playing a role in ethylene production after harvest by enhancing ACC synthase, which is inhibited as long as the fruit is attached to the tree (Sitrit et al, 1986;Hershkovitz et al, 2010).…”

“…Additional MADS-box genes were also discovered in other fleshy fruit: apple (Yao et al, 1999), grape (Boss et al, 2001), peach (Tadiello et al, 2009), tomato (Busi et al, 2003;Itkin et al, 2009), Chinese pear (Yamane et al, 2007) and banana (Elitzur et al, 2010). In avocado, the MADS-box genes have been identified and examined in floral development (Kim et al, 2004), but not in fruit ripening.…”

Fleshy Fruit Expansion and Ripening Are Regulated by the Tomato SHATTERPROOF Gene TAGL1

“…However, it has not been reported as to whether PLENA can rescue the Arabidopsis shp1 shp2 fruit dehiscence phenotype. Furthermore, overexpression of the peach (Prunus persica) ortholog of TAGL1 in tomato can result in sepal expansion and carotenoid accumulation but does not result in any apparent homeotic conversions of petals (Tadiello et al, 2009). Together, these results argue that there has been considerable plasticity in the ways in which these orthologous proteins from Antirrhinum majus, tomato, peach, and Arabidopsis perform their functions, which may depend in part on their protein interaction partners as well as subtle differences in their expression patterns during flower and fruit development.…”

“…The latter include the tomato MADS-RIN MADS box (Vrebalov et al, 2002;Ito et al, 2008), Colorless nonripening (Cnr) SPB box (Manning et al, 2006), and HB-1 homeobox (Lin et al, 2008) genes that are all necessary for ethylene induction and ripening in tomato. Though most ripening regulators defined to date have not been demonstrated to impact fruit fleshiness, ectopic expression of homologous and heterologous genes encoding MADS box and HD-ZIP transcription factors in tomato has resulted in fleshy sepal development and pigmentation suggestive of ripening (e.g., lycopene accumulation) in these altered floral organs (Pnueli et al, 1994b;Lin et al, 2008;Tadiello et al, 2009).…”

Regulatory Mechanisms Underlying Oil Palm Fruit Mesocarp Maturation, Ripening, and Functional Specialization in Lipid and Carotenoid Metabolism

“…Another common regulatory feature of fruit has emerged from functional analyses with the MADS box family of transcription factors (TFs), including RIN and TOMATO AGAMOUS-LIKE1 (TAGL1) from tomato, PLENA from peach (Prunus persica), and FaMADS9 from strawberry (Fragaria 3 ananassa), which have provided evidence for roles during ripening (Vrebalov et al, 2002(Vrebalov et al, , 2009Tadiello et al, 2009;Seymour et al, 2011). The recent identification of diverse MADS expressed during banana (Musa acuminata) ripening raises the questions of whether the function of some MADS box proteins is common to monocots and whether divergence occurred after the separation of dicots and monocots (Liu et al, 2009;Elitzur et al, 2010).…”