The establishment of agricultural economies based upon domestic animals began independently in many parts of the world and led to both increases in human population size and the migration of people carrying domestic plants and animals. The precise circumstances of the earliest phases of these events remain mysterious given their antiquity and the fact that subsequent waves of migrants have often replaced the first. Through the use of more than 1,500 modern (including 151 previously uncharacterized specimens) and 18 ancient (representing six East Asian archeological sites) pig (Sus scrofa) DNA sequences sampled across East Asia, we provide evidence for the long-term genetic continuity between modern and ancient Chinese domestic pigs. Although the Chinese case for independent pig domestication is supported by both genetic and archaeological evidence, we discuss five additional (and possibly) independent domestications of indigenous wild boar populations: one in India, three in peninsular Southeast Asia, and one off the coast of Taiwan. Collectively, we refer to these instances as "cryptic domestication," given the current lack of corroborating archaeological evidence. In addition, we demonstrate the existence of numerous populations of genetically distinct and widespread wild boar populations that have not contributed maternal genetic material to modern domestic stocks. The overall findings provide the most complete picture yet of pig evolution and domestication in East Asia, and generate testable hypotheses regarding the development and spread of early farmers in the Far East.Asian colonization | mtDNA | phylogeography

Chickens represent by far the most important poultry species, yet the number, locations, and timings of their domestication have remained controversial for more than a century. Here we report ancient mitochondrial DNA sequences from the earliest archaeological chicken bones from China, dating back to ∼10,000 B.P. The results clearly show that all investigated bones, including the oldest from the Nanzhuangtou site, are derived from the genus Gallus, rather than any other related genus, such as Phasianus. Our analyses also suggest that northern China represents one region of the earliest chicken domestication, possibly dating as early as 10,000 y B.P. Similar to the evidence from pig domestication, our results suggest that these early domesticated chickens contributed to the gene pool of modern chicken populations. Moreover, our results support the idea that multiple members of the genus Gallus, specifically Gallus gallus and Gallus sonneratii contributed to the gene pool of the modern domestic chicken. Our results provide further support for the growing evidence of an early mixed agricultural complex in northern China.ancient DNA | chicken | domestication | species origin

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Entomopathogenic fungus as well as their toxins is a natural threat surrounding social insect colonies. To defend against them, social insects have evolved a series of unique disease defenses at the colony level, which consists of behavioral and physiological adaptations. These colony-level defenses can reduce the infection and poisoning risk and improve the survival of societal members, and is known as social immunity. In this review, we discuss how social immunity enables the insect colony to avoid, resist and tolerate fungal pathogens. To understand the molecular basis of social immunity, we highlight several genetic elements and biochemical factors that drive the colony-level defense, which needs further verification. We discuss the chemosensory genes in regulating social behaviors, the antifungal secretions such as some insect venoms in external defense and the immune priming in internal defense. To conclude, we show the possible driving force of the fungal toxins for the evolution of social immunity. Throughout the review, we propose several questions involved in social immunity extended from some phenomena that have been reported. We hope our review about social ‘host–fungal pathogen’ interactions will help us further understand the mechanism of social immunity in eusocial insects.

Hedgehog (Hh) signaling, via the key signal transducer Smoothened (SMO) and Gli transcription factors, is essential for embryonic development and carcinogenesis. At present, the molecular mechanism of Hh signaling-mediated carcinogenesis is not completely understood. Using a mouse model (K14cre/ R26SmoM2) of SMO-mediated basal cell carcinoma development, we identified TGF␤2 as a major Hh-regulated gene. TGF␤2 expression was high in the keratinocytes, with activated TGF␤ signaling (indicated by elevated expression of phosphorylated SMAD2/3) detected in both tumor and stroma. The significance of TGF␤ signaling for SMO function was demonstrated in two assays. Down-regulation of TGF␤2 expression prevented Hh signaling-dependent osteoblast differentiation and motor neuron differentiation. Furthermore, inhibition of TGF␤ signaling by TGF␤ receptor I inhibitor SD208 significantly reduced tumor area in K14cre/R26SmoM2 mice. Tumor shrinkage in mice was associated with an increased number of lymphocytes, suggesting an immune suppression role of TGF␤ signaling. The relevance of our results to human cancer is reflected by the fact that human basal cell carcinomas, which almost always harbor activated Hh signaling, have activated TGF␤ signaling, as indicated by high levels of phosphorylated SMAD2 and SMAD3 in tumor and stroma. Together, our data indicate that TGF␤ signaling is critical for Hh signaling-mediated carcinogenesis.The Hedgehog pathway plays an important role in cell differentiation, tissue polarity, cell proliferation, and carcinogenesis (1-4). The seven-transmembrane domain-containing protein Smoothened (SMO) 4 serves as the key player for signal transduction of this pathway, whose function is inhibited by another transmembrane protein, Patched (PTC), in the absence of Hh ligands. Binding of Hh to its receptor PTC releases this inhibition, allowing SMO to signal downstream, leading to formation of active forms of Gli transcription factors. As transcription factors, Gli molecules can regulate target gene expression by direct association with a specific consensus sequence located at the promoter region of the target genes (5). In addition to the canonical pathways (ligand overexpression, altered expression of Hh signaling molecules, or gene mutations), recent studies indicate that Hh signaling can also be activated by other signaling pathways, such as K-Ras. Both canonical and non-canonical Hh signaling activation are found in many types of human cancer, including brain tumors, gastrointestinal, prostate, lung, and breast cancers (6 -8).Mounting evidence indicates that Hh signaling activation occurs frequently in a number of human cancers (9), but the underlying molecular basis remains largely elusive. To understand the molecular basis by which Hh signaling regulates carcinogenesis, we analyzed gene expression of a mouse model of basal cell carcinoma in which an activated form of SMO (SmoM2) replaces the wild type SMO allele and is expressed under the control of the keratin 14 promoter. Our results indicated that ...

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The mitochondrial DNA of 172 sheep from 48 families were typed by using PCR-RFLP, direct amplification of the repeated sequence domain and sequencing analysis. The mitochondrial DNA from three lambs in two half-sib families were found to show paternal inheritance. Our findings provide direct evidence of paternal inheritance of mitochondria DNA in sheep. A total of 12 highly polymorphic microsatellite markers, which mapped on different chromosomes, were employed to type the sheep population to confirm family relationships. Possible mechanisms of paternal inheritance are discussed.