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The genome of soybean ( Glycine max ), a commercially important crop, has recently been sequenced and is one of six crop species to have been sequenced. Here we report the genome sequence of G. soja , the undomesticated ancestor of G. max (in particular, G. soja var. IT182932). The 48.8-Gb Illumina Genome Analyzer (Illumina-GA) short DNA reads were aligned to the G. max reference genome and a consensus was determined for G. soja . This consensus sequence spanned 915.4 Mb, representing a coverage of 97.65% of the G. max published genome sequence and an average mapping depth of 43-fold. The nucleotide sequence of the G. soja genome, which contains 2.5 Mb of substituted bases and 406 kb of small insertions/deletions relative to G. max , is ∼0.31% different from that of G. max . In addition to the mapped 915.4-Mb consensus sequence, 32.4 Mb of large deletions and 8.3 Mb of novel sequence contigs in the G. soja genome were also detected. Nucleotide variants of G. soja versus G. max confirmed by Roche Genome Sequencer FLX sequencing showed a 99.99% concordance in single-nucleotide polymorphism and a 98.82% agreement in insertion/deletion calls on Illumina-GA reads. Data presented in this study suggest that the G. soja / G. max complex may be at least 0.27 million y old, appearing before the relatively recent event of domestication (6,000∼9,000 y ago). This suggests that soybean domestication is complicated and that more in-depth study of population genetics is needed. In any case, genome comparison of domesticated and undomesticated forms of soybean can facilitate its improvement.

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Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder characterized by loss of motor neurons. Dominant mutations in the gene for superoxide dismutase 1 (SOD1) give rise to familial ALS by an unknown mechanism. Here we show that genetic deficiency of mammalian sterile 20-like kinase 1 (MST1) delays disease onset and extends survival in mice expressing the ALS-associated G93A mutant of human SOD1. SOD1(G93A) induces dissociation of MST1 from a redox protein thioredoxin-1 and promotes MST1 activation in spinal cord neurons in a reactive oxygen species-dependent manner. Moreover, MST1 was found to mediate SOD1(G93A)-induced activation of p38 mitogen-activated protein kinase and caspases as well as impairment of autophagy in spinal cord motoneurons of SOD1(G93A) mice. Our findings implicate MST1 as a key determinant of neurodegeneration in ALS.neurotoxicity | ROS A myotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disorder characterized by the selective loss of motor neurons in the brain and spinal cord. Whereas most cases (∼90%) of ALS are sporadic (sALS), both sALS and familial ALS (fALS) share similar clinical characteristics, suggestive of common disease mechanisms. Mutations in the gene for superoxide dismutase 1 (SOD1) are one of the most common causes of fALS and give rise to disease as a result of acquired gain-offunction toxicity (1, 2). Studies using the disease-model mice overexpressing ALS-linked mutants of human SOD1 have suggested that many mutations result in oxidative damage and apoptosis in motor neurons (2, 3). The molecular mechanism by which SOD1 mutants induce neurodegeneration remains unclear, however.Mammalian sterile 20 (STE20)-like kinase 1 (MST1) is a multifunctional serine-threonine kinase that belongs to the family of class II germinal center kinases (4-6). MST1 is composed of a catalytic domain in the amino-terminal region, an inhibitory domain in the central region, and a regulatory Salvador/ Rassf/Hippo (SARAH) domain in the carboxyl-terminal region (7,8). The SARAH domain is responsible for the homo-dimerization of MST1, which contributes to the mechanism underlying MST1 activation (7, 9). It also mediates the formation of heteromeric complexes with other SARAH domain-containing proteins such as 45 kDa WW domain protein and Rassf proteins (7,8). MST1 is expressed ubiquitously and is associated with the regulatory mechanisms for many biological events including cell growth, apoptosis, stress response, and senescence (10, 11). In particular, MST1 has been recently suggested to mediate neuronal cell death initiated by oxidative stress (11,12).Given that oxidative stress contributes to the pathogenesis of ALS, we investigated the possible role of MST1 in the neurotoxicity underlying fALS with use of a transgenic mouse model. Results and DiscussionMotor Neurons in sALS Patients and SOD1(G93A) Mice Show Higher Activity of MST1. We first examined MST1 activity in primary motor neurons (PMNs) prepared from the spinal cord of E13 embryos of contro...

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The Fas pathway and oxidative stress mediate neuronal death in stroke and may contribute to neurodegenerative disease. We tested the hypothesis that these two factors synergistically produce spinal motor neuron degeneration in amyotrophic lateral sclerosis (ALS

Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disease characterized by the selective degeneration of upper and lower motor neurons associated with the abnormal aggregation of ubiquitinated proteins. The molecular mechanisms underlying the pathogenesis of ALS remain unclear, however. Autophagy is a major pathway for the elimination of protein aggregates and damaged organelles and therefore contributes to cellular homeostasis. This catabolic process begins with the formation of the double membrane-bound autophagosome that engulfs portions of the cytoplasm and subsequently fuses with a lysosome to form an autolysosome, in which lysosomal enzymes digest autophagic substrates. Defects at various stages of autophagy have been associated with pathological mutations of several ALS-linked genes including SOD1, p62, TDP-43, and optineurin, suggesting that such defects may play a causative role in the pathogenesis of this condition. In this review, we summarize the dysregulation of autophagy associated with ALS as well as potential therapeutic strategies based on modulation of the autophagic process.

Background: Soybean lipoxygenases (Lxs) play important roles in plant resistance and in conferring the distinct bean flavor. Lxs comprise a multi-gene family that includes GmLx1, GmLx2 and GmLx3, and many of these genes have been characterized. We were interested in investigating the relationship between the soybean lipoxygenase isozymes from an evolutionary perspective, since soybean has undergone two rounds of polyploidy. Here we report the tetrad genome structure of soybean Lx regions produced by ancient and recent polyploidy. Also, comparative genomics with Medicago truncatula was performed to estimate Lxs in the common ancestor of soybean and Medicago.