Growing cells of Campylobacter coli and C. jejuni were naturally transformed by naked DNA without the requirement for any special treatment. Transformation frequencies for homologous chromosomal DNA were approximately 10(-3) transformants per recipient cell in C. coli and 10(-4) in C. jejuni. Maximum competence was found in the early log phase of growth. Campylobacters preferentially took up their own DNA in comparison with Escherichia coli chromosomal DNA, which was taken up very poorly. Three new Campylobacter spp.-to-E. coli shuttle plasmids, which contained additional cloning sites and selectable markers, were constructed from the shuttle vector pILL550A. These plasmid DNAs were taken up by campylobacters much less efficiently than was homologous chromosomal DNA, and transformation into plasmid-free cells was very rare. However, with the use of recipients containing a homologous plasmid, approximately 10(-4) transformants per cell were obtained. The tetM determinant, originally obtained from Streptococcus spp. and not heretofore reported in Campylobacter spp., was isolated from an E. coli plasmid and was introduced, selecting for tetracycline resistance, by natural transformation into C. coli.

Bread wheat expanded its habitats from a small core area of the Fertile Crescent to global environments within ~10,000 years. Genetic mechanisms of this remarkable evolutionary success are not well understood. By whole-genome sequencing of populations from 25 subspecies within genera Triticum and Aegilops, we identified composite introgression from these wild populations contributing 13%~36% of the bread wheat genome, which tremendously increased the genetic diversity of bread wheat and allowed its divergent adaptation. Meanwhile, convergent adaption to human selection showed 2-to 16-fold enrichment relative to random expectation in Triticum species despite their drastic differences in ploidy levels and growing zones, indicating the vital importance of adaptive constraints in the success of bread wheat. These results showed the genetic necessities of wheat as a global crop and provided new perspectives on leveraging adaptation success across species for crop improvement.

Long noncoding RNAs (lncRNAs) are essential regulators of gene expression in eukaryotes. Despite increasing knowledge on the function of lncRNAs, little is known about their effects on crop yield. Here, we identify a lncRNA transcribed from the antisense strand of neighbouring gene LRK (leucine-rich repeat receptor kinase) cluster named LAIR (LRK Antisense Intergenic RNA). LAIR overexpression increases rice grain yield and upregulates the expression of several LRK genes. Additionally, chromatin immunoprecipitation assay results indicate H3K4me3 and H4K16ac are significantly enriched at the activated LRK1 genomic region. LAIR binds histone modification proteins OsMOF and OsWDR5 in rice cells, which are enriched in LRK1 gene region. Moreover, LAIR is demonstrated to bind 5′ and 3′ untranslated regions of LRK1 gene. Overall, this study reveals the role of lncRNA LAIR in regulating rice grain yield and lncRNAs may be useful targets for crop breeding.

We report the observation of liquid-liquid phase separation in a solution of human monoclonal antibody, IgG2, and the effects of human serum albumin, a major blood protein, on this phase separation. We find a significant reduction of phase separation temperature in the presence of albumin, and a preferential partitioning of the albumin into the antibody-rich phase. We provide a general thermodynamic analysis of the antibody-albumin mixture phase diagram and relate its features to the magnitude of the effective interprotein interactions. Our analysis suggests that additives (HSA in this report), which have moderate attraction with antibody molecules, may be used to forestall undesirable proetin condensation in antibody solutions. Our findings are relevant to understanding the stability of pharmaceutical solutions of antibodies and the mechanisms of cryoglobulinemia.ntibodies are widely used in research and biotechnology, as well as in medical and pharmaceutical applications. In some cases, concentrated solutions of specific antibodies are required. In particular, monoclonal antibodies (MAb) have become a major category of drugs in the treatment of a variety of diseases (1). In some drug delivery routes e.g., subcutaneous administration, formulations with concentrated antibody solutions are required to achieve therapeutic dosing (2).The physiological functions of antibodies are mostly determined by antibody-antigen and antibody-receptor specific interactions. However, the nonspecific interactions between antibodies (i.e., self-association) in the concentrated antibody solutions can also affect their functions. Nonspecific attractive interactions can cause various forms of condensation, including liquid-liquid phase separation, aggregation, and crystallization. Upon such condensation, antibodies lose their solubility, and may lose their biological activity. Particularly, in pharmaceutical industry, these processes impact storage stability and safety of protein therapeutics thus impeding drug development (3). For example, immunogenicity of some biologics has been attributed to formation of protein aggregates (4). The mechanisms of protein condensation are complex and depend on protein concentration, buffer composition, temperature, etc. Clearly, the factors which affect protein condensation throughout the shelf-life must be understood and controlled to ensure biotherapeutic effectiveness.One important condensation process is liquid-liquid phase separation (LLPS). In LLPS, a homogeneous protein solution spontaneously separates into two coexisting phases with different protein concentrations. This phenomenon takes place upon changing the temperature or other solution conditions, and is reversible. In contrast to aggregation or crystallization, LLPS, while highly sensitive to the average "net" attractive interaction between proteins, are much less sensitive to the distribution pattern and the nature of the "local" interactions on the protein surface. As a result, LLPS exhibits universal features applicable to a variety...