enome, suggesting critical function but an inability to innovate. The largely prokaryotic CAK family is also functionally and structurally diverse, containing several known functions and PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/19859661 many distinct subfamilies likely to have novel functions. The diversity of both CAK 
and KdoK sequences may be related to their involvement in antibiotic resistance and immune evasion, likely to be evolutionarily accelerated processes. Comparison of CAK to the related and more functionally constrained HSK2, FruK, and MTRK families may reveal adaptive changes such as the ePK-specific flexibility changes that may assist in its diversity of functions. GOS data are rich in highly divergent viral sequences, and accordingly we find a number of new subfamilies of viral kinases, including two of the three subfamilies of HRK and a subfamily of CapK. In both cases we see loss of N-terminalconserved elements, suggesting that these kinases may have alternative functions or even act as inactive competitors to host kinases. These patterns of sequence conservation and diversity raise many questions that can only be fully addressed by structural methods. The combination of structural and phylogenetic insights for ChoK enabled insights that were not clear from the structure alone, and enabled us to reject other inferences from the crystal structure that were not conserved within this family, highlighting the value of combining these approaches. The relative ease of crystallization of PKL domains, the emergence of high-throughput structural genomics, and our understanding of the diversity of these families make them attractive targets for structure determination of selected members, and position this family as a model for analysis of deep structural and functional evolution. Materials and Methods Discovery and classification of kinase genes. Sequences used consisted of 17,422,766 open reading frames from GOS, 3,049,695 predicted open reading frames from prokaryotic genomes, and 2,317,995 protein sequences from NCBI-nr of February 10, 2005, as described. Profile HMM searches were performed with a Time Logic Decypher system using inhouse profiles for ePK, Haspin, Bub1, Bud32, Rio, ABC1, PI3K, and AlphaK domains, as well as Pfam profiles for ChoK, APH, KdoK, and FruK, and TIGRFAM profiles for HSK2, UbiB, and MTRK. A number of additional ePK-annotated models from Superfamily 1.67 were used to capture initial hits but not for further classification. Initial hits were clustered and re-run against all models, and each model was rebuilt and rerun three to seven times using ClustalW, MUSCLE, and hmmalign to align, followed by manual adjustment of alignments using Clustal and Pfaat and model building with hmmbuild. Lowscoring members of each family were used as seeds to build new putative families, and profileprofile and sequenceprofile alignments were used to merge families into a minimal set. It has been suggested that these transport vesicles fuse at sites of nascent synapse formation to deliver protein constituents of the AZ in a site-specific manner. Although transport vesicles have not been isolated in Drosophila motoneurons, it was recently demonstrated that mutation of a Kinesin 3 prevents the transport of synaptic vesicle proteins to the developing synapse, SRPK-Dependent GSK126 manufacturer Control of T-Bar Assembly Author Summary Neurons communicate with each other through electrochemical impulses transmitted primarily at specialized intercellular junctions termed synapses. At each synapse,