Genome-Wide Transcript Profiling of Endosperm without Paternal Contribution Identifies Parent-of-Origin–Dependent Regulation of AGAMOUS-LIKE36

Abstract

Seed development in angiosperms is dependent on the interplay among different transcriptional programs operating in the embryo, the endosperm, and the maternally-derived seed coat. In angiosperms, the embryo and the endosperm are products of double fertilization during which the two pollen sperm cells fuse with the egg cell and the central cell of the female gametophyte. In Arabidopsis, analyses of mutants in the cell-cycle regulator CYCLIN DEPENDENT KINASE A;1 (CKDA;1) have revealed the importance of a paternal genome for the effective development of the endosperm and ultimately the seed. Here we have exploited cdka;1 fertilization as a novel tool for the identification of seed regulators and factors involved in parent-of-origin–specific regulation during seed development. We have generated genome-wide transcription profiles of cdka;1 fertilized seeds and identified approximately 600 genes that are downregulated in the absence of a paternal genome. Among those, AGAMOUS-LIKE (AGL) genes encoding Type-I MADS-box transcription factors were significantly overrepresented. Here, AGL36 was chosen for an in-depth study and shown to be imprinted. We demonstrate that AGL36 parent-of-origin–dependent expression is controlled by the activity of METHYLTRANSFERASE1 (MET1) maintenance DNA methyltransferase and DEMETER (DME) DNA glycosylase. Interestingly, our data also show that the active maternal allele of AGL36 is regulated throughout endosperm development by components of the FIS Polycomb Repressive Complex 2 (PRC2), revealing a new type of dual epigenetic regulation in seeds.

Arabidopsis LORELEI, a Maternally Expressed Imprinted Gene, Promotes Early Seed Development

“…Nevertheless, our study adds LRE to a growing list of MEGs whose loss negatively impacts seed development, including ZIX, FH5, and NUWA in Arabidopsis (Ingouff et al, 2005;Fitz Gerald et al, 2009;Ngo et al, 2012;He et al, 2017) and MEG1 in maize (Gutiérrez-Marcos et al, 2004;Costa et al, 2012). Additionally, mutations in MEGs like FWA and AGL36 do not result in endosperm phenotypes (Kinoshita et al, 2004;Shirzadi et al, 2011). These MEGs highlight the need to explore alternative theories for imprinting.…”

Isolation and characterization of a copalyl diphosphate synthase gene promoter from Salvia miltiorrhiza

“…3) [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60]. Comparison of the obtained data with trans-factors identified by the in silico searches of S. miltiorrhiza CPS promoter showed no common protein (Tab.…”

“…The results of in silico searches and microarray co-expression studies differ with regard to plant morphogenesis. While the in silico studies suggest that CPS promoter has a potential role in plant embryogenesis and leaf development, the microarray co-expression tests indicate that the CPS promoter has potential participation in a broader range of morphogenesis processes as pollen, sieve, seed, ovule, and gametophyte development [25,28,[44][45][46][47][48][49][50][51].…”

“…The microarray data implied a role of A. thaliana CPS in development of such elements as pollen, sieve, seed, ovule, and gametophyte (Tab. 3) [44,[46][47][48][49][50][51]. According to the in silico searches, the S. miltiorrhiza CPS promoter should participate rather in leaf development (Tab.…”

Early Disruption of Maternal–Zygotic Interaction and Activation of Defense-Like Responses inArabidopsisInterspecific Crosses

“…AGL proteins, such as AGL62, play an important role in endosperm development (Kang et al, 2008;Shirzadi et al, 2011), and differential regulation of AGL genes is associated with deleterious effects in interspecific-interploidy Arabidopsis hybrid fitness (Josefsson et al, 2006;Walia et al, 2009). We found that 10 AGLs, including the previously documented endosperm cluster, were differentially expressed between the Col-0 hybrid and C24 hybrid seed (see Supplemental Table 8 online).…”