Porphyra umbilicalis (laver) belongs to an ancient group of red algae (Bangiophyceae), is harvested for human food, and thrives in the harsh conditions of the upper intertidal zone. Here we present the 87.7-Mbp haploid Porphyra genome (65.8% G + C content, 13,125 gene loci) and elucidate traits that inform our understanding of the biology of red algae as one of the few multicellular eukaryotic lineages. Novel features of the Porphyra genome shared by other red algae relate to the cytoskeleton, calcium signaling, the cell cycle, and stress-tolerance mechanisms including photoprotection. Cytoskeletal motor proteins in Porphyra are restricted to a small set of kinesins that appear to be the only universal cytoskeletal motors within the red algae. Dynein motors are absent, and most red algae, including Porphyra, lack myosin. This surprisingly minimal cytoskeleton offers a potential explanation for why red algal cells and multicellular structures are more limited in size than in most multicellular lineages. Additional discoveries further relating to the stress tolerance of bangiophytes include ancestral enzymes for sulfation of the hydrophilic galactan-rich cell wall, evidence for mannan synthesis that originated before the divergence of green and red algae, and a high capacity for nutrient uptake. Our analyses provide a comprehensive understanding of the red algae, which are both commercially important and have played a major role in the evolution of other algal groups through secondary endosymbioses.cytoskeleton | calcium-signaling | carbohydrate-active enzymes | stress tolerance | vitamin B 12T he red algae are one of the founding groups of photosynthetic eukaryotes (Archaeplastida) and among the few multicellular lineages within Eukarya. A red algal plastid, acquired through secondary endosymbiosis, supports carbon fixation, fatty acid synthesis, and other metabolic needs in many other algal groups in ways that are consequential. For example, diatoms and haptophytes have strong biogeochemical effects; apicomplexans cause human disease (e.g., malaria); and dinoflagellates include both coral symbionts and toxin-producing "red tides" (1). The evolutionary processes that produced the Archaeplastida and secondary algal lineages remain under investigation (2-5), but it is clear that both nuclear and plastid genes from the ancestral red algae have contributed dramatically to broader eukaryotic evolution and diversity. Consequently, the imprint of red algal metabolism on the Earth's climate system, aquatic foodwebs, and

Human Vγ9/Vδ2 T cells comprise a small population of peripheral blood T cells that in many infectious diseases respond to the microbial metabolite, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), expanding to up to 50% of CD3+ cells. This “transitional response,” occurring temporally between the rapid innate and slower adaptive response, is widely viewed as proinflammatory and/or cytolytic. However, increasing evidence that different cytokines drive widely different effector functions in αβ T cells provoked us to apply cDNA microarrays to explore the potential pleiotropy of HMB-PP-activated Vγ9/Vδ2 T cells. The data and accompanying validations show that the related cytokines, IL-2, IL-4, or IL-21, each drive proliferation and comparable CD69 up-regulation but induce distinct effector responses that differ from prototypic αβ T cell responses. For example, the Th1-like response to IL-2 also includes expression of IL-5 and IL-13 that conversely are not induced by IL-4. The data identify specific molecules that may mediate γδ T cell effects. Thus, IL-21 induces a lymphoid-homing phenotype and high, unexpected expression of the follicular B cell-attracting chemokine CXCL13/BCA-1, suggesting a novel follicular B-helper-like T cell that may play a hitherto underappreciated role in humoral immunity early in infection. Such broad plasticity emphasizes the capacity of γδ T cells to influence the nature of the immune response to different challenges and has implications for the ongoing clinical application of cytokines together with Vγ9/Vδ2 TCR agonists.

The high degree of morphological plasticity displayed by species of the brown algal genus Fucus L. is well documented. Such variation is especially pronounced for those estuarine taxa lacking holdfasts (termed ecads) that often bear little resemblance to the attached species from which they are derived. To better understand the systematics of salt marsh fucoids, we developed a suite of four microsatellite‐containing loci capable of distinguishing between F. vesiculosus L. and F. spiralis L. The genetic markers were used to determine the relationships of the fucoid ecads F. vesiculosus ecad volubilis (Hudson) Turner and a muscoides‐like Fucus in the Brave Boat Harbor (ME, USA) estuary. Ecad populations had 2‐ to 3‐fold higher levels of heterozygosity than attached populations of F. vesiculosus and F. spiralis. Further, ecads were “intermediate” between F. vesiculosus and F. spiralis in their allele frequencies and genotype composition. Our data indicate that populations of muscoides‐like Fucus in Brave Boat Harbor mainly consist of F1 hybrids between F. vesiculosus and F. spiralis, whereas F. vesiculosus ecad volubilis may arise through backcrosses between F. vesiculosus and other fertile hybrids. Finally, our data support the hypothesis that introgression has occurred between attached populations of F. vesiculosus and F. spiralis.

Background:Truly phosphospecific antibodies are difficult to generate and are poorly understood. Results: Avian single chain Fv library selections yielded fully phosphospecific anti-phospho-tau antibodies, enabling the generation of a 1.9 Å co-crystal structure. Conclusion: Phosphospecific antibodies were readily generated and can exhibit unique epitope recognition mechanisms. Significance: High-affinity antibody phosphoepitope recognition has been defined, at high resolution, for the first time.

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