@article{18942,
  abstract     = {Photosynthesis is among the first processes negatively affected by environmental cues and its performance directly determines plant cell fitness and ultimately crop yield. Primarily sites of photosynthesis, chloroplasts are unique sites also for the biosynthesis of precursors of the growth regulator auxin and for sensing environmental stress, but their role in intracellular auxin homeostasis, vital for plant growth and survival in changing environments, remains poorly understood. Here, we identified two ATP-binding cassette (ABC) subfamily B transporters, ABCB28 and ABCB29, which export auxin across the chloroplast envelope to the cytosol in a concerted action in vivo. Moreover, we provide evidence for an auxin biosynthesis pathway in Arabidopsis thaliana chloroplasts. The overexpression of ABCB28 and ABCB29 influenced stomatal regulation and resulted in significantly improved water use efficiency and survival rates during salt and drought stresses. Our results suggest that chloroplast auxin production and transport contribute to stomata regulation for conserving water upon salt stress. ABCB28 and ABCB29 integrate photosynthesis and auxin signals and as such hold great potential to improve the adaptation potential of crops to environmental cues.},
  author       = {Tamizhselvan, Prashanth and Madhavan, Sharmila and Constan-Aguilar, Christian and Elrefaay, Eman Ryad and Liu, Jie and Pěnčík, Aleš and Novák, Ondřej and Cairó, Albert and Hrtyan, Mónika and Geisler, Markus and Tognetti, Vanesa Beatriz},
  issn         = {2223-7747},
  journal      = {Plants},
  number       = {1},
  publisher    = {MDPI},
  title        = {{Chloroplast auxin efflux mediated by ABCB28 and ABCB29 fine-tunes salt and drought stress responses in Arabidopsis}},
  doi          = {10.3390/plants13010007},
  volume       = {13},
  year         = {2023},
}

@article{7582,
  abstract     = {Small RNAs (smRNA, 19–25 nucleotides long), which are transcribed by RNA polymerase II, regulate the expression of genes involved in a multitude of processes in eukaryotes. miRNA biogenesis and the proteins involved in the biogenesis pathway differ across plant and animal lineages. The major proteins constituting the biogenesis pathway, namely, the Dicers (DCL/DCR) and Argonautes (AGOs), have been extensively studied. However, the accessory proteins (DAWDLE (DDL), SERRATE (SE), and TOUGH (TGH)) of the pathway that differs across the two lineages remain largely uncharacterized. We present the first detailed report on the molecular evolution and divergence of these proteins across eukaryotes. Although DDL is present in eukaryotes and prokaryotes, SE and TGH appear to be specific to eukaryotes. The addition/deletion of specific domains and/or domain-specific sequence divergence in the three proteins points to the observed functional divergence of these proteins across the two lineages, which correlates with the differences in miRNA length across the two lineages. Our data enhance the current understanding of the structure–function relationship of these proteins and reveals previous unexplored crucial residues in the three proteins that can be used as a basis for further functional characterization. The data presented here on the number of miRNAs in crown eukaryotic lineages are consistent with the notion of the expansion of the number of miRNA-coding genes in animal and plant lineages correlating with organismal complexity. Whether this difference in functionally correlates with the diversification (or presence/absence) of the three proteins studied here or the miRNA signaling in the plant and animal lineages is unclear. Based on our results of the three proteins studied here and previously available data concerning the evolution of miRNA genes in the plant and animal lineages, we believe that miRNAs probably evolved once in the ancestor to crown eukaryotes and have diversified independently in the eukaryotes.},
  author       = {Moturu, Taraka Ramji and Sinha, Sansrity and Salava, Hymavathi and Thula, Sravankumar and Nodzyński, Tomasz and Vařeková, Radka Svobodová and Friml, Jiří and Simon, Sibu},
  issn         = {2223-7747},
  journal      = {Plants},
  number       = {3},
  publisher    = {MDPI},
  title        = {{Molecular evolution and diversification of proteins involved in miRNA maturation pathway}},
  doi          = {10.3390/plants9030299},
  volume       = {9},
  year         = {2020},
}