Immunological identification of complex proteins resolved by sodium dodecyl sulfate polyacrylamide disc gel electrophoresis.

Immunological identification of an antigen resolved from a protein complex by sodium dodecyl sulfate polyacrylamide gel electrophoresis has been attained. The identification is based on the formation of immunoprecipitin lines after the antigen diffuses laterally from acrylamide gel transverse slices into a surrounding agarose gel. This technique was designed for study of contractile and regulatory protein complexes of non-muscle cells where the scarcity of tissue precludes easy purification or high yield of muscle-like proteins. It complements double-gel immunodiffusion or immunoelectrophoresis and its use may be extended to other protein complexes.     

The DNA-binding activity of the Neisseria gonorrhoeae LexA orthologue NG1427 is modulated by oxidation

Neisseria gonorrhoeae is a human-specific organism that is not usually exposed to UV light or chemicals but is likely to encounter reactive oxygen species during infection. Exposure of N. gonorrhoeae to sublethal hydrogen peroxide revealed that the ng1427 gene was upregulated sixfold. N. gonorrhoeae was thought to lack an SOS system, although NG1427 shows amino acid sequence similarity to the SOS response regulator LexA from Escherichia coli. Similar to LexA and other S24 peptidases, NG1427 undergoes autoproteolysis in vitro, which is facilitated by either the gonococcal or E. coli RecA proteins or high pH, and autoproteolysis requires the active and cleavage site residues conserved between LexA and NG1427. NG1427 controls a three gene regulon: itself; ng1428, a Neisseria-specific, putative integral membrane protein; and recN, a DNA repair gene known to be required for oxidative damage survival. Full NG1427 regulon de-repression requires RecA following methyl methanesulphonate or mitomycin C treatment, but is largely RecA-independent following hydrogen peroxide treatment. NG1427 binds specifically to the operator regions of the genes it controls, and DNA binding is abolished by oxidation of the single cysteine residue encoded in NG1427. We propose that NG1427 is inactivated independently of RecA by oxidation.     

Allerton III. Beyond livestock genomics

Throughout the Allerton III Conference, several consistent research needs were identified across scientific disciplines. First, additional basic research is needed to identify genomic mechanisms and novel genes/proteins in a variety of tissues under different conditions. Second, expansion of the infrastructure of the scientific community is needed. This can best be accomplished by additional competitive grants programs for training grants, program project grants, and multidisciplinary research projects. Third, the need for improved tools for animal bioinformatics was emphasized. Fourth, competitive grants programs for extension/outreach efforts and application of genomic technologies to production systems are needed. Finally, efforts to publicize and document the benefits of animal genomics for improved human health and animal production systems to members of Congress and the general public should be enhanced.     

Swine Genome Sequencing Consortium (SGSC): a strategic roadmap for sequencing the pig genome

The Swine Genome Sequencing Consortium (SGSC) was formed in September 2003 by academic, government and industry representatives to provide international coordination for sequencing the pig genome. The SGSC's mission is to advance biomedical research for animal production and health by the development of DNAbased tools and products resulting from the sequencing of the swine genome. During the past 2 years, the SGSC has met bi-annually to develop a strategic roadmap for creating the required scientific resources, to integrate existing physical maps, and to create a sequencing strategy that captured international participation and a broad funding base. During the past year, SGSC members have integrated their respective physical mapping data with the goal of creating a minimal tiling path (MTP) that will be used as the sequencing template. During the recent Plant and Animal Genome meeting (January 16, 2005 San Diego, CA), presentations demonstrated that a human-pig comparative map has been completed, BAC fingerprint contigs (FPC) for each of the autosomes and X chromosome have been constructed and that BAC end-sequencing has permitted, through BLAST analysis and RH-mapping, anchoring of the contigs. Thus, significant progress has been made towards the creation of a MTP. In addition, whole-genome (WG) shotgun libraries have been constructed and are currently being sequenced in various laboratories around the globe. Thus, a hybrid sequencing approach in which 3x coverage of BACs comprising the MTP and 3x of the WG-shotgun libraries will be used to develop a draft 6x coverage of the pig genome.     

Comparison of calmodulin binding to brain synaptic and coated vesicles

Several characteristics of calmodulin association with brain synaptic and coated vesicles were analyzed and compared. Radioimmunoassay revealed that both classes of vesicles contain approx. 1 μg of calmodulin per mg of vesicle protein. Discontinuous sucrose gradients revealed that coated and synaptic vesicles preparations were homogeneous and had different sedimentation properties. Binding of ¹²⁵I-labeled calmodulin to synaptic and coated vesicles was Ca²⁺ dependent and displaced by unlabeled calmodulin but not by troponin-C. Scatchard analysis revealed the presence of two binding sites. In both vesicle types there was one high-affinity, low-binding-capacity site ($\text{K}{}_{\mathrm{<mtext>d</mtext>}}\text{= 1–39}\text{nM and B}{}_{\mathrm{<mtext>max</mtext>}}\text{= 4–16}\text{pmol}\text{/}\text{mg}$) and one low-affinity, high-binding-capacity site ($\text{K}{}_{\mathrm{<mtext>d</mtext>}}\text{= 102–177}\text{nM and B}{}_{\mathrm{<mtext>max</mtext>}}\text{= 151–202}\text{pmol}\text{/}\text{mg}$). (Ca²⁺ + Mg²⁺)-ATPase activity was stimulated in both synaptic and coated vesicles by calmodulin. Thus synaptic and coated vesicles may possess similar calmodulin binding sites.     

Survey of Genomics Approaches to Improve Bioenergy Traits in Maize,Sorghum and Sugarcane

Bioenergy crops currently provide the only source of alternative energy with the potential to reduce the use of fossil transportation fuels in a way that is compatible with existing engine technology,including in developing countries.Even though bioenergy research is currently receiving considerable attention,many of the concepts are not new,but rather build on intense research efforts from 30 years ago.A major difference with that era is the availability of genomics tools that have the potential to acceler...     

Interval mapping of growth in divergent swine cross

A genomic scan of 18 swine autosomal chromosomes was constructed with 119 polymorphic microsatellite (ms) markers to identify quantitative trait loci (QTL) for 11 growth traits in the University of Illinois Meishan × Yorkshire Swine Resource Family. A significant QTL effect was found for post-weaning average daily gain (ADG) between 5.5 and 56 kg of body weight that mapped between markers SW373 and SW1301 near the telomere of Chromosome (Chr) 1 q (SSC1). This QTL effect had a nominal (pointwise) p-value of 0.000007, a genome wide p-value of 0.012, and accounted for 26% of the F₂ phenotypic variance. The same chromosome region also had significant effects on ADG between birth and 56 kg body weight (p-value = .000227), and on ADG between 35 and 56 kg (p-value = .00077). These observations suggest that a significant QTL for post-weaning growth resides on SSC1. Received: 18 May 1998 / Accepted: 6 October 1998