TY  - JOUR
A1  - Zhang, Yunming
A1  - Ramming, Anna
A1  - Heinke, Lisa
A1  - Altschmied, Lothar
A1  - Slotkin, R. Keith
A1  - Becker, Jörg D.
A1  - Kappel, Christian
A1  - Lenhard, Michael
T1  - The poly(A) polymerase PAPS1 interacts with the RNA-directed DNA-methylation pathway in sporophyte and pollen development
JF  - The plant journal
N2  - RNA-based processes play key roles in the regulation of eukaryotic gene expression. This includes both the processing of pre-mRNAs into mature mRNAs ready for translation and RNA-based silencing processes, such as RNA-directed DNA methylation (RdDM). Polyadenylation of pre-mRNAs is one important step in their processing and is carried out by three functionally specialized canonical nuclear poly(A) polymerases in Arabidopsis thaliana. Null mutations in one of these, termed PAPS1, result in a male gametophytic defect. Using a fluorescence-labelling strategy, we have characterized this defect in more detail using RNA and small-RNA sequencing. In addition to global defects in the expression of pollen-differentiation genes, paps1 null-mutant pollen shows a strong overaccumulation of transposable element (TE) transcripts, yet a depletion of 21- and particularly 24-nucleotide-long short interfering RNAs (siRNAs) and microRNAs (miRNAs) targeting the corresponding TEs. Double-mutant analyses support a specific functional interaction between PAPS1 and components of the RdDM pathway, as evident from strong synergistic phenotypes in mutant combinations involving paps1, but not paps2 paps4, mutations. In particular, the double-mutant of paps1 and rna-dependent rna polymerase 6 (rdr6) shows a synergistic developmental phenotype disrupting the formation of the transmitting tract in the female gynoecium. Thus, our findings in A. thaliana uncover a potentially general link between canonical poly(A) polymerases as components of mRNA processing and RdDM, reflecting an analogous interaction in fission yeast.
KW  - poly(A) polymerase
KW  - RNA-directed DNA methylation
KW  - pollen development
KW  - siRNAs
KW  - transposable elements
KW  - gynoecium development
KW  - Arabidopsis thaliana
Y1  - 2019
U6  - https://doi.org/10.1111/tpj.14348
SN  - 0960-7412
SN  - 1365-313X
VL  - 99
IS  - 4
SP  - 655
EP  - 672
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Cuong Nguyen Huu, 
A1  - Kappel, Christian
A1  - Keller, Barbara
A1  - Sicard, Adrien
A1  - Takebayashi, Yumiko
A1  - Breuninger, Holger
A1  - Nowak, Michael D.
A1  - Bäurle, Isabel
A1  - Himmelbach, Axel
A1  - Burkart, Michael
A1  - Ebbing-Lohaus, Thomas
A1  - Sakakibara, Hitoshi
A1  - Altschmied, Lothar
A1  - Conti, Elena
A1  - Lenhard, Michael
T1  - Presence versus absence of CYP734A50 underlies the style-length dimorphism in primroses
JF  - eLife
N2  - Heterostyly is a wide-spread floral adaptation to promote outbreeding, yet its genetic basis and evolutionary origin remain poorly understood. In Primula (primroses), heterostyly is controlled by the S-locus supergene that determines the reciprocal arrangement of reproductive organs and incompatibility between the two morphs. However, the identities of the component genes remain unknown. Here, we identify the Primula CYP734A50 gene, encoding a putative brassinosteroid-degrading enzyme, as the G locus that determines the style-length dimorphism. CYP734A50 is only present on the short-styled S-morph haplotype, it is specifically expressed in S-morph styles, and its loss or inactivation leads to long styles. The gene arose by a duplication specific to the Primulaceae lineage and shows an accelerated rate of molecular evolution. Thus, our results provide a mechanistic explanation for the Primula style-length dimorphism and begin to shed light on the evolution of the S-locus as a prime model for a complex plant supergene.
Y1  - 2016
U6  - https://doi.org/10.7554/eLife.17956
SN  - 2050-084X
VL  - 5
PB  - eLife Sciences Publications
CY  - Cambridge
ER  -