C5L2 is critical for the biological activities of the anaphylatoxins C5a and C3a

Complement-derived anaphylatoxins regulate immune and inflammatory responses through G-protein-coupled receptor (GPCR)-mediated signalling. C5L2 (also known as GPR77) is a relatively new GPCR thought to be a non-signalling receptor binding to C5a, on the basis of sequence information and experimental evidence. Here we show, using gene targeting, that C5L2 is required to facilitate C5a signalling in neutrophils, macrophages and fibroblasts in vitro. Deficiency of C5L2 results in reduced inflammatory cell infiltration, suggesting that C5L2 is critical for optimal C5a-mediated cell infiltration in certain in vivo settings. C5L2 is also involved in optimizing C3a-induced signals. Furthermore, like mice incapable of C3a/complement 3a receptor (C3aR) signalling, C5L2-deficient mice are hypersensitive to lipopolysaccharide (LPS)-induced septic shock, show reduced ovalbumin (OVA)-induced airway hyper-responsiveness and inflammation, and are mildly delayed in haematopoietic cell regeneration after gamma-irradiation. Our data indicate that C5L2 can function as a positive modulator for both C5a- and C3a-anaphylatoxin-induced responses.     

Agrobacterium-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass ( Agrostis palustris Huds. ) cv. Regent and colonial bentgrass ( Agrostis Tenuis Sibth. F1. Oxen. ) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4-7 days and then co-cultivated with Agrobacterium tumefaciens, LBA4404,which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR) . After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12-15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2-3 months of selection, the actively growing calli of ‘Regent‘ and ‘Ti-ger‘ were transferred to MS medium with 12-15 mg/L PPT and 250 mg/L cefotaxime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4 % of herbi-cide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.     

Jelly belly protein activates the receptor tyrosine kinase Alk to specify visceral muscle pioneers

The secreted protein Jelly belly (Jeb) is required for an essential signalling event in Drosophila muscle development. In the absence of functional Jeb, visceral muscle precursors are normally specified but fail to migrate and differentiate. The structure and distribution of Jeb protein implies that Jeb functions as a signal to organize the development of visceral muscles. Here we show that the Jeb receptor is the Drosophila homologue of anaplastic lymphoma kinase (Alk), a receptor tyrosine kinase of the insulin receptor superfamily. Human ALK was originally identified as a proto-oncogene, but its normal function in mammals is not known. In Drosophila, localized Jeb activates Alk and the downstream Ras/mitogen-activated protein kinase cascade to specify a select group of visceral muscle precursors as muscle-patterning pioneers. Jeb/Alk signalling induces the myoblast fusion gene dumbfounded (duf; also known as kirre) as well as org-1, a Drosophila homologue of mammalian TBX1, in these cells.     

Glucocorticoids regulate expression of dihydrofolate reductase cDNA in mouse mammary tumour virus chimaeric plasmids

Fusions between the mouse mammary tumour virus long terminal repeat and a mouse dihydrofolate reductase cDNA have been constructed in a SV40 vector. When these plasmids are transferred into recipient cells, the production of dihydrofolate reductase is regulated by glucocorticoid hormones. These results define a hormonally responsive region of the viral genome.     

Accurate prediction of the stability and activity effects of site-directed mutagenesis on a protein core.

Theoretical prediction of the structure, stability and activity of proteins, an important unsolved problem in molecular biology, would be of use for guiding site-directed mutagenesis and other protein-engineering techniques. X-ray diffraction studies have provided extensive structural information for many proteins, challenging theorists to develop reliable techniques able to use such knowledge as a base for prediction of mutants' characteristics. Here we report theoretical calculation of stabilization energies for 78 triple-site sequence variants of lambda repressor characterized experimentally by Lim and Sauer. The calculated energies correlate with the mutants' measured activities; active and inactive mutations are discriminated with 92% reliability. They correlate even more directly with the mutants' thermostabilities, correctly identifying two of the mutants to be more stable than the wild type.     

Modern optics in exceptionally preserved eyes of Early Cambrian arthropods from Australia

Despite the status of the eye as an "organ of extreme perfection", theory suggests that complex eyes can evolve very rapidly. The fossil record has, until now, been inadequate in providing insight into the early evolution of eyes during the initial radiation of many animal groups known as the Cambrian explosion. This is surprising because Cambrian Burgess-Shale-type deposits are replete with exquisitely preserved animals, especially arthropods, that possess eyes. However, with the exception of biomineralized trilobite eyes, virtually nothing is known about the details of their optical design. Here we report exceptionally preserved fossil eyes from the Early Cambrian (～ 515 million years ago) Emu Bay Shale of South Australia, revealing that some of the earliest arthropods possessed highly advanced compound eyes, each with over 3,000 large ommatidial lenses and a specialized 'bright zone'. These are the oldest non-biomineralized eyes known in such detail, with preservation quality exceeding that found in the Burgess Shale and Chengjiang deposits. Non-biomineralized eyes of similar complexity are otherwise unknown until about 85 million years later. The arrangement and size of the lenses indicate that these eyes belonged to an active predator that was capable of seeing in low light. The eyes are more complex than those known from contemporaneous trilobites and are as advanced as those of many living forms. They provide further evidence that the Cambrian explosion involved rapid innovation in fine-scale anatomy as well as gross morphology, and are consistent with the concept that the development of advanced vision helped to drive this great evolutionary event.     

Network anatomy and in vivo physiology of visual cortical neurons

In the cerebral cortex, local circuits consist of tens of thousands of neurons, each of which makes thousands of synaptic connections. Perhaps the biggest impediment to understanding these networks is that we have no wiring diagrams of their interconnections. Even if we had a partial or complete wiring diagram, however, understanding the network would also require information about each neuron's function. Here we show that the relationship between structure and function can be studied in the cortex with a combination of in vivo physiology and network anatomy. We used two-photon calcium imaging to characterize a functional property--the preferred stimulus orientation--of a group of neurons in the mouse primary visual cortex. Large-scale electron microscopy of serial thin sections was then used to trace a portion of these neurons' local network. Consistent with a prediction from recent physiological experiments, inhibitory interneurons received convergent anatomical input from nearby excitatory neurons with a broad range of preferred orientations, although weak biases could not be rejected.