University of Freiburg Plant Biotechnology Group Hosts MOSS 2004 Conference

By Aldwin Anterola

The 7th Annual Moss International Conference was held in the University of Freiburg, Germany on Sept. 12-15, 2004, and was attended by 120 participants (a 2-fold increase from last year) from Australia, Austria, Belgium, France, Germany, Israel, Japan, Sweden, Switzerland, United Kingdom, United States, and Uruguay.

Newcomers and old-timers alike, as well as famous pioneers in moss research, gathered together in the friendly city of Freiburg to exchange recent results, new techniques and novel ideas through seminars, posters, workshops and lab tours. Social interaction among scientists and students (see an informal essay written by a student participant) was also facilitated by night-time events, such as a guided city tour, conference dinner, wine-tasting, and a mountain hike at the Black Forest. The most important event in the conference, however, was the launching of the MOSS genome project, which is an international collaborative effort spearheaded by laboratories in Germany (Ralf Reski), Japan (Mitsuyasu Hasebe), United Kingdom (David Cove and Andrew Cuming) and United States (Brent Mishler and Ralph Quatrano). A special workshop was held during the conference to discuss the details of how to proceed with this undertaking (see separate article by Brent Mishler on the proceedings of this workshop).

On the first day of the conference (Sept. 12), participants were greeted with a warm welcome by the Plant Biotechnology Crew, headed by Ralf Reski, who along with his committee organized this year's conference.

As host, Prof. Reski gave informative opening remarks, describing interesting facts about Freiburg and its scientific legacy. He also introduced distinguished guests, which included Martin Bopp and Wolfgang Abel, both of whom were considered pioneers of moss research in Germany (who also happen to be the "scientific grandfather and father" of Ralf Reski, respectively). Please note: The picture depicts Ralf Reski, Martin Bopp and David Cove, NOT Wolfgang Abel). 

David Cove then gave an enlightening (and oftentimes humorous) personal account of developments in moss research over the course of his (still active) scientific career, which amazingly revealed interesting interconnections among the attendees in the conference. This welcome reception ended with an entertaining, and at the same time educational, surprise presentation by Michael Lüth, who displayed quite a spectacle of beautiful pictures and artistic renditions of mosses, accompanied by an upbeat music at the background, thus providing a unique audio-visual treat for everyone.

The first session (Sept. 13) got off at a good start with a comprehensive lecture on EvoDevo studies given by Mitsuyasu Hasebe, in which he discussed the modular model of development and how their lab is using Physcomitrella to address this hypothesis (see history of Physcomitrella research in Japan). This was then followed by talks about Physcomitrella transcription factors involved in development, which were presented by Thomas Münster (MADS-box genes), Takako Tanahashi (LEAFY genes) and Tomoaki Nishiyama (KNOX genes), respectively.

The second session afterwards started with a "cool and refreshing" lecture on mosses that grow in Antarctica, and how researchers brave the extreme conditions in this remote continent to study the evolution and survival of its flora and fauna. This was presented by Mary Skotnicki, who herself went to the Antarctic region to study cold-adapted mosses. A lively presentation was then given by Mark von Stackelberg on genetic studies of different ecotypes of Physcomitrella, which aimed at constructing a genetic map of this model organism. A thought-provoking talk on crosses made on Ceratodon purpureus was then presented by Stuart McDaniel (see Stuart's personal essay), who wanted to understand the genetic basis of protonemal development. Plastids then came to the limelight as Hiroyoshi Takano and Nancy Hoffman discussed plastid peptidoglycan biosynthesis and chloroplast protein targeting in Physcomitrella, respectively.

The next day (Sept. 14) David Cove gave a talk on molecular mechanisms in homologous recombinantion, followed by Didier Schaefer presenting his recent work on Agrobacterium-mediated transformation of Physcomitrella. These two speakers are known for their landmark contributions to moss research. They, along with Jeane-Pierre Zryd and Celia Knight, are credited for developing efficient transformation protocols for Physcomitrella, which represents a breakthrough in this field. Additionally, David Cove is known for his extensive genetic studies of Physcomitrella, whereas Didier Schaefer is made famous by his discovery of homologous recombination (while working under Jean-Pierre Zryd), arguably the most important feature of Physcomitrella as a genetic model organism.

In the same session, Bénédicte Trouiller, who works in the lab of Fabien Nogué, presented results of their studies in cytokinin signaling in Physcomitrella. Like most other talks in this conference, this one involved a broad international collaboration (France, Japan and Switzerland), which is not uncommon in moss research. This is one example of how open scientists are in this community in terms of cooperating with each other, and pooling together resources in order to accomplish more than they could individually. Such a cordial atmosphere is evident in how participants of MOSS 2004 interact with one another during the conference.

Plastids took center-stage again when Mamoru Sugita gave an engaging presentation on plastid transformation in Physcomitrella. As with the other talks, a spirited discussion ensued, which was characterized by a dynamic exchange of ideas stemming from questions posed by enthusiastic participants. This session ended with an update on the moss transcriptome provided by Stefan Rensing, who is also one of the key persons in the organizing committee, and a senior member in the laboratory of Ralf Reski.

The next session consisted of very interesting topics, which started with a presentation by Aldwin Anterola on mammalian-like lipoxygenases in moss and their potential biomedical relevance. This was followed by Gertrud Wiedeman's talk on sulfate reduction in the sulfate assimilation pathway of Physcomitrella, and how it compares to the corresponding pathways in other plant species.

Eva Decker then presented results of recent experiments involving the modification of N-glycosylation patterns in Physcomitrella in order to generate lines suitable for the production of therapeutic proteins. Kieran Lee discussed the highlights of his Ph.D. thesis, as he talked about arabinogalactan proteins and their role in cell wall assembly. At the end of this session, Yoshikatsu Sato showed impressive cinematic images of filament reorganization and chloroplast movement generated by 4D microscopy. A variety of topics have therefore been covered in this session, which represents the expanding breadth of moss research, perhaps transcending even beyond the expectations of the initial pioneers in this field.

The last day (Sept. 15) was equally exciting as the previous ones. The first session began with Ralph Quatrano giving an overview of ABA signaling in plants and an update of the experiments undertaken in his lab in order to understand ABA-regulated gene expression in moss and seed plants. Setsuyuki Aoki then presented temporal expression data on lhcb genes of Physcomitrella, and suggested that moss had a circadian rhythm different from those of seed plants.

Michael Lawton introduced a new "buzz word" in the moss community (physcopathology), which describes his research in Physcomitrella, being the "study of interactions between Physcomitrella and potential pathogens." He presented evidence for the presence of programmed cell death pathways and defense responses in Physcomitrella, which appeared to be similar to that found in seed plants. At the end of this session, Magdalena Bezanilla presented her work on RNAi silencing and how she used this technology to study myosin function. Like homologous recombination, this method is expected to be useful to other researchers in this field intent on performing functional genomics studies on Physcomitrella, especially with genes having multiple copies in the moss genome.

The last session focused on studies of abiotic stress using moss (Physcomitrella and Tortula ruralis) as model system. Moss is an appropriate model system for such studies since these plants are known to be extremely tolerant to dehydration. Indeed, in his seminar about rehydration-induced transcripts of Tortula ruralis, Melvin Oliver showed a slide where Tortula regained its normal morphology even after dessication, simply by imbibing water (see Melvin Oliver's article). In a related study, Andrew Wood employed EST analysis to arrive at a TrDr3 gene, which is putatively involved in dessication-tolerance in Tortula. Wolfgang Frank and Andrew Cuming, on the other hand, use Physcomitrella as their model system. Wolfgang Frank exposed Physcomitrella to salt, osmotic and dehydration stress, and looked at the expression patterns of homologous stress-associated genes. Andrew Cuming described a number of ABA regulated genes including a late embryogenesis abundant (LEA) gene that may act via a nonsense-mediated mRNA degradation pathway to regulate stress response in Physcomitrella.

The conference formally concluded with a short farewell speech from Ralf Reski, acknowledging all the people who helped made the conference a huge success. He also asked for feedback/comments from the participants regarding the conduct of the conference. Poster awards were then given three students, namely Valentina Carballo, Tina Olsson and Andrija Finka, who, among the 40 poster nominees, received the most votes from the participants. These students received a cash award, courtesy of the sponsors.