[fod] FoD Seminar: John Mattick (IMB) Thu 29 Nov

[Janet Wiles <janetw@itee.uq.edu.au>]

This seminar is in the Festival of Doubt series. FoD is a weekly
gathering of researchers with an interest in biologically inspired
intelligent machines. http://www.festivalofdoubt.uq.edu.au/

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Speaker: Prof. John Mattick, IMB
Title:	 The evolution of controlled multitasked gene networks:
	 the role of introns and other non-coding RNAs in the
	 development of complex organisms
Date:	 Thursday 29th Nov, 4pm
Room:	 GP-South rm 226

<bold><italic>Summary

</italic></bold>Eukaryotic phenotypic diversity arises from
multitasking of a core proteome of limited size. Multitasking is
routine in computers, as well as in other sophisticated information
systems, and requires multiple inputs and outputs to control and
integrate network activity. Higher eukaryotes have a mosaic gene
structure with a dual output, mRNA (protein-coding) sequences and
introns, which are released from the pre-mRNA by posttranscriptional
processing.  Introns have been enormously successful as a class of
sequences and comprise up to 95% of the primary transcripts of
protein-coding genes in mammals. In addition, many other transcripts
(perhaps more than half) do not encode proteins at all, but appear both
to be developmentally regulated and to have genetic function. We
suggest that these RNAs (eRNAs) have evolved to function as endogenous
network control molecules which enable direct gene-gene communication
and multitasking of eukaryotic genomes. Analysis of a range of complex
genetic phenomena in which RNA is involved or implicated, including
co-suppression, transgene silencing, RNA interference, imprinting,
methylation, and transvection, suggests that a higher-order regulatory
system based on RNA signals operates in the higher eukaryotes and
involves chromatin remodeling as well as other RNA-DNA, RNA-RNA, and
RNA-protein interactions. The evolution of densely connected gene
networks would be expected to result in a relatively stable core
proteome due to the multiple reuse of components, implying that
cellular differentiation and phenotypic variation in the higher
eukaryotes results primarily from variation in the control
architecture. Thus, network integration and multitasking using
<italic>trans</italic>-acting RNA molecules produced in parallel with
protein-coding sequences may underpin both the evolution of
developmentally sophisticated multicellular organisms and the rapid
expansion of phenotypic complexity into uncontested environments such
as those initiated in the Cambrian radiation and those seen after major
extinction events. This system has interesting and perhaps informative
analogies with small world networks and dataflow computing.

The evolution of controlled multitasked gene networks: the role of
introns and other non-coding RNAs in the development of complex
organisms"