STY1 and STY2 promote the formation of apical tissues during Arabidopsis gynoecium development

Gynoecium ontogenesis in Arabidopsis is accomplished by the co-ordinated activity of genes that control patterning and the regional differentiation of tissues, and ultimately results in the formation of a basal ovary, a short style and an apical stigma. A transposon insertion in the STYLISH1 (STY1) gene results in gynoecia with aberrant style morphology, while an insertion mutation in the closely related STYLISH2 (STY2) gene has no visible effect on gynoecium development. However, sty1-1 sty2-1 double mutant plants exhibit an enhanced sty1-1 mutant phenotype and are characterized by a further reduction in the amount of stylar and stigmatic tissues and decreased proliferation of stylar xylem. These data imply that STY1 and STY2 are partially redundant and that both genes promote style and stigma formation and influence vascular development during Arabidopsis gynoecium development. Consistently, STY1 and STY2 are expressed in the apical parts of the developing gynoecium and ectopic expression of either STY1 or STY2 driven by the CaMV 35S promoter is sufficient to transform valve cells into style cells. STY1::GUS and STY2::GUS activity is detected in many other organs as well as the gynoecium, suggesting that STY1 and STY2 may have additional functions. This is supported by the sty1-1 sty2-1 double mutants producing rosette and cauline leaves with a higher degree of serration than wild-type leaves. STY1 and STY2 are members of a small gene family, and encode proteins with a RING finger-like motif. Double mutant analyses indicate that STY1 genetically interacts with SPATULA and possibly also with CRABS CLAW

Variations on the Theme of Information Literacy – Implementation of Information Literacy into the First-Year Curriculum at Åbo Akademi University

How can information literacy (IL) courses be organized into the curriculum in the best possible way for first-year students at Finnish universities? This question has been discussed time and time again. At Åbo Akademi University we have, since fall 2015, developed a course in Academic study skills where IL is included in the course. This means that IL is now for the first time included in all study programmes at the university. The IL module is, however, implemented in different ways in different faculties. In this article, we will focus on the method of embedded learning of IL in the study programme of Chemical Engineering, as it was implemented during the fall semester 2015 for all freshmen. For the first time the library was involved in a “hands-on” project with practical tasks at the Faculty of Science and Engineering. The students were motivated to learn how to search for information and how to improve their skills in reference management, and they passed the course

Dependence on clade II bHLH transcription factors for nursing of haploid products by tapetal-like cells is conserved between moss sporangia and angiosperm anthers

Clade II basic helix-loop-helix transcription factors (bHLH TFs) are essential for pollen production and tapetal nursing functions in angiosperm anthers. As pollen has been suggested to be related to bryophyte spores by descent, we characterized two Physcomitrium (Physcomitrella) patens clade II bHLH TFs (PpbHLH092 and PpbHLH098), to test if regulation of sporogenous cells and the nursing cells surrounding them is conserved between angiosperm anthers and bryophyte sporangia. We made CRISPR-Cas9 reporter and loss-of-function lines to address the function of PpbHLH092/098. We sectioned and analyzed WT and mutant sporophytes for a comprehensive stage-by-stage comparison of sporangium development. Spore precursors in the P. patens sporangium are surrounded by nursing cells showing striking similarities to tapetal cells in angiosperms. Moss clade II bHLH TFs are essential for the differentiation of these tapetal-like cells and for the production of functional spores. Clade II bHLH TFs provide a conserved role in controlling the sporophytic somatic cells surrounding and nursing the sporogenous cells in both moss sporangia and angiosperm anthers. This supports the hypothesis that such nursing functions in mosses and angiosperms, lineages separated by roughly 450 million years, are related by descent

Developing an organic research agenda with stakeholder involvement promotes increased relevance in research

A Swedish organic research agenda was developed by EPOK, Centre for Organic Food and Farming, in an open process together with interested parties in the food chain. The main aim of the research agenda was to provide a well-supported document which would enable decision makers and research funding bodies prioritise future research calls. The agenda took on the most important future challenges and knowledge needs of the organic food chain on the road towards increased sustainability, efficiency and environmental and social benefits. Three cross-cutting themes were identified to describe the overall challenges that face organic agriculture and the organic food chain: Robust systems, Added value for the environment and society and Competitiveness and thriving rural communities. Based of the three overarching themes five prioritised focal areas were pointed out in the research agenda: 1) High productivity with maintained sustainability, 2) Innovative production systems with many functions, 3) Closed-loop cycles and renewable resources, 4) Sustainable enterprises and market development, 5) Healthy food with added value. Involving stakeholders in forming the research agenda promoted early interactions and cooperation between actors within organic agricultural research. Furthermore the involvement of numerous stakeholders enabled a broad view of the need for new knowledge in the organic food chain, from primary production and marketing questions to the performance of organic agriculture in respect of beneficial contribution to environment and society. A dialogue with researchers and agricultural research funding bodies was an important part of the process forming the agenda. The consequence of this cooperation was that the agenda has been used as a basis of a number of research calls

MS1/MMD1 homologues in the moss Physcomitrium patens are required for male and female gametogenesis

The Arabidopsis Plant HomeoDomain (PHD) proteins AtMS1 and AtMMD1 provide chromatin-mediated transcriptional regulation essential for tapetum-dependent pollen formation. This pollen-based male gametogenesis is a derived trait of seed plants. Male gametogenesis in the common ancestors of land plants is instead likely to have been reminiscent of that in extant bryophytes where flagellated sperms are produced by an elaborate gametophyte generation. Still, also bryophytes possess MS1/MMD1-related PHD proteins. We addressed the function of two MS1/MMD1-homologues in the bryophyte model moss Physcomitrium patens by the generation and analysis of reporter and loss-of-function lines. The two genes are together essential for both male and female fertility by providing functions in the gamete-producing inner cells of antheridia and archegonia. They are furthermore expressed in the diploid sporophyte generation suggesting a function during sporogenesis, a process proposed related by descent to pollen formation in angiosperms. We propose that the moss MS1/MMD1-related regulatory network required for completion of male and female gametogenesis, and possibly for sporogenesis, represent a heritage from ancestral land plants

Studies of moss reproductive development indicate that auxin biosynthesis in apical stem cells may constitute an ancestral function for focal growth control

The plant hormone auxin is a key factor for regulation of plant development, and this function was probably reinforced during the evolution of early land plants. We have extended the available toolbox to allow detailed studies of how auxin biosynthesis and responses are regulated in moss reproductive organs, their stem cells and gametes to better elucidate the function of auxin in the morphogenesis of early land plants. We measured auxin metabolites and identified IPyA (indole-3-pyruvic acid) as the main biosynthesis pathway inPhyscomitrium(Physcomitrella)patensand established knock-out, overexpressor and reporter lines for biosynthesis genes which were analyzed alongside previously reported auxin-sensing and transport reporters. Vegetative and reproductive apical stem cells synthesize auxin. Sustained stem cell activity depends on an inability to sense the auxin produced while progeny of the stem cells respond to the auxin, aiding in the control of cell division, expansion and differentiation. Gamete precursors are dependent on a certain degree of auxin sensing, while the final differentiation is a low auxin-sensing process. Tha data presented indicate that low auxin activity may represent a conserved hallmark of land plant gametes, and that local auxin biosynthesis in apical stem cells may be part of an ancestral mechanism to control focal growth

Ekologisk produktion med minskad klimatpåverkan

Jordbruket har möjlighet att förutom att minska sina egna utsläpp även bidra till övriga samhällets omställning genom produktion av bioenergi och inlagring av kol i mark. Många av det ekologiska jordbrukets klimatutmaningar är gemensamma för alla typer av jordbruk. Men ekologisk produktion bygger på ett antal principer som tar sig uttryck i ett regelverk, vilket skapar specifika förutsättningar för det ekologiska jordbrukets möjligheter att minska sina växthusgasutsläpp. Här sammanfattas viktiga områden när det gäller klimatpåverkan från ekologiskt jordbruk