Two recurrent themes throughout the conference were 1) the limits of detection by sequence-only based methods, and 2) the apparent extreme complexity of the LECA, the Last Eukaryotic Common Ancestor. This was best illustrated by MC Field in his contribution entitled "Finding things that are not there - lessons at the nuclear envelope". He demonstrated that a combination of molecular biology experiments combined with bioinformatics, essentially structural predictions, were able to detect proteins that could not be detected by Blast searches. This was illustrated in the case of the nuclear pore complex of the trypanosome. Of course, in this case, extreme care has to be taken to discriminate the real signal from the noise. He extended his analysis from the nuclear pore complex to the transporter that ensure the transfer of the cargo through the nuclear envelope, the karyopherins. He showed that karyopherins are conserved and ancient, with at least 14 being most likely present in the LECA, again adding to the complexity of this elusive ancestor. Eventually concluding on the detection of things that are not there, he showed conclusive data about the presence of Lamin analogue in Trypanosome which was so far thought not to possess such an intranuclear protein (a work in press in PLoS Biology).
On a related theme, but different organism, Margaret 'Rossie' Robinson presented her last work on the detection of a new, the fifth, adaptor complex, AP5. The list of adaptor complex was thought to be complete, prompting some article title like 'Adaptins: the final recount' (MBoC 2001). It is genuine to wonder about how many such discovery are still awaiting out there.
MP Rout then presented his work on the structure of the nuclear pore complex by integrative modeling. I won't go back to the details of the work published in 2007, but they have pushed the limits of the method to achieve a model of a major building block of the complex, the so-called Nup84 complex, to a precision of ~1.5 nm. This amazing work has just been published in JCB (Fernandez-Martinez et al., 2012). The suggestions derived from the structure about a possible ancestral two fold symmetry at the core of the Nup84 complex was very inspiring and very much in line of the evolution of the nuclear pore complex and thus the protocoatomer hypothesis.
It is so beautiful that I can't resist to show you the inspiring figure taken from the publication
You can see the possible axis of duplication and the losses of the Nup85/Seh1 equivalent, as well as the reductive loss of Nup84 Nt-domain and Sec13 equivalent. Very inspiring.
On a related theme, but different organism, Margaret 'Rossie' Robinson presented her last work on the detection of a new, the fifth, adaptor complex, AP5. The list of adaptor complex was thought to be complete, prompting some article title like 'Adaptins: the final recount' (MBoC 2001). It is genuine to wonder about how many such discovery are still awaiting out there.
MP Rout then presented his work on the structure of the nuclear pore complex by integrative modeling. I won't go back to the details of the work published in 2007, but they have pushed the limits of the method to achieve a model of a major building block of the complex, the so-called Nup84 complex, to a precision of ~1.5 nm. This amazing work has just been published in JCB (Fernandez-Martinez et al., 2012). The suggestions derived from the structure about a possible ancestral two fold symmetry at the core of the Nup84 complex was very inspiring and very much in line of the evolution of the nuclear pore complex and thus the protocoatomer hypothesis.
It is so beautiful that I can't resist to show you the inspiring figure taken from the publication
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