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Together, our data show that K383 in PopP2 represents an acetyl-CoA binding site that is (i) targeted by autoacetylation and (ii) required for intermolecular acetylation of PopP2. In the revised version, the above issues have been addressed by reporting data from different replicates in different figure panels, clearly indicating where an image was spliced in preparing the figure, and replacing the Fig 7A results with the replication results for which supporting data are in S6 File. [Extracted from the article]

Background and Purpose: There are no generally accepted criteria for the etiologic classification of intracerebral hemorrhage (ICH). For this reason, we have developed a set of etiologic criteria and have applied them to a large number of patients to determine their utility. Methods: The H-ATOMIC classification includes 7 etiologic categories: Hypertension, cerebral Amyloid angiopathy, Tumour, Oral anticoagulants, vascular Malformation, Infrequent causes and Cryptogenic. For each category, the etiology is scored with three degrees of certainty: Possible(3), Probable(2) and Definite(1). Our aim was to perform a basic study consisting of neuroimaging, blood tests, and CT-angio when a numerical score (SICH) suggested an underlying structural abnormality. Combinations of >1 etiologic category for an individual patient were acceptable. The criteria were evaluated in a multicenter and prospective study of consecutive patients with spontaneous ICH. Results: Our study included 439 patients (age 70.8 ± 14.5 years; 61.3% were men). A definite etiology was achieved in 176 (40.1% of the patients: Hypertension 28.2%, cerebral Amyloid angiopathy 0.2%, Tumour 0.2%, Oral anticoagulants 2.2%, vascular Malformation 4.5%, Infrequent causes 4.5%). A total of 7 patients (1.6%) were cryptogenic. In the remaining 58.3% of the patients, ICH was attributable to a single (n = 56, 12.7%) or the combination of ≥2 (n = 200, 45.5%) possible/probable etiologies. The most frequent combinations of etiologies involved possible hypertension with possible CAA (H3A3, n = 38) or with probable CAA (H3A2, n = 29), and probable hypertension with probable OA (H2O2, n = 27). The most frequent category with any degree of certainty was hypertension (H1+2+3 = 80.6%) followed by cerebral amyloid angiopathy (A1+2+3 = 30.9%). Conclusions: According to our etiologic criteria, only about 40% patients received a definite diagnosis, while in the remaining patients ICH was attributable to a single possible/probable etiology or to more than one possible/probable etiology. The use of these criteria would likely help in the management of patients with ICH. [ABSTRACT FROM AUTHOR]

The failure of gene-for-gene resistance traits to provide durable and broad-spectrum resistance in an agricultural context has led to the search for genes underlying quantitative resistance in plants. Such genes have been identified in only a few cases, all for fungal or nematode resistance, and encode diverse molecular functions. However, an understanding of the molecular mechanisms of quantitative resistance variation to other enemies and the associated evolutionary forces shaping this variation remain largely unknown. We report the identification, map-based cloning and functional validation of QRX3 (RKS1, Resistance related KinaSe 1), conferring broad-spectrum resistance to Xanthomonas campestris (Xc), a devastating worldwide bacterial vascular pathogen of crucifers. RKS1 encodes an atypical kinase that mediates a quantitative resistance mechanism in plants by restricting bacterial spread from the infection site. Nested Genome-Wide Association mapping revealed a major locus corresponding to an allelic series at RKS1 at the species level. An association between variation in resistance and RKS1 transcription was found using various transgenic lines as well as in natural accessions, suggesting that regulation of RKS1 expression is a major component of quantitative resistance to Xc. The co-existence of long lived RKS1 haplotypes in A. thaliana is shared with a variety of genes involved in pathogen recognition, suggesting common selective pressures. The identification of RKS1 constitutes a starting point for deciphering the mechanisms underlying broad spectrum quantitative disease resistance that is effective against a devastating and vascular crop pathogen. Because putative RKS1 orthologous have been found in other Brassica species, RKS1 provides an exciting opportunity for plant breeders to improve resistance to black rot in crops. [ABSTRACT FROM AUTHOR]

Background: The SCN5A encoded sodium current (INa) generates the action potential (AP) upstroke and is a major determinant of AP characteristics and AP propagation in cardiac myocytes. Unfortunately, in cardiac myocytes, investigation of kinetic properties of INa with near-physiological ion concentrations and temperature is technically challenging due to the large amplitude and rapidly activating nature of INa, which may seriously hamper the quality of voltage control over the membrane. We hypothesized that the alternating voltage clamp-current clamp (VC/CC) technique might provide an alternative to traditional voltage clamp (VC) technique for the determination of INa properties under physiological conditions. Principal Findings: We studied INa under close-to-physiological conditions by VC technique in SCN5A cDNA-transfected HEK cells or by alternating VC/CC technique in both SCN5A cDNA-transfected HEK cells and rabbit left ventricular myocytes. In these experiments, peak INa during a depolarizing VC step or maximal upstroke velocity, dV/dtmax, during VC/CC served as an indicator of available INa. In HEK cells, biophysical properties of INa, including current density, voltage dependent (in)activation, development of inactivation, and recovery from inactivation, were highly similar in VC and VC/CC experiments. As an application of the VC/CC technique we studied INa in left ventricular myocytes isolated from control or failing rabbit hearts. Conclusions: Our results demonstrate that the alternating VC/CC technique is a valuable experimental tool for INa measurements under close-to-physiological conditions in cardiac myocytes. [ABSTRACT FROM AUTHOR]

Type III effector proteins from bacterial pathogens manipulate components of host immunity to suppress defence responses and promote pathogen development. In plants, host proteins targeted by some effectors called avirulence proteins are surveyed by plant disease resistance proteins referred to as "guards". The Ralstonia solanacearum effector protein PopP2 triggers immunity in Arabidopsis following its perception by the RRS1-R resistance protein. Here, we show that PopP2 interacts with RRS1-R in the nucleus of living plant cells. PopP2 belongs to the YopJ-like family of cysteine proteases, which share a conserved catalytic triad that includes a highly conserved cysteine residue. The catalytic cysteine mutant PopP2-C321A is impaired in its avirulence activity although it is still able to interact with RRS1-R. In addition, PopP2 prevents proteasomal degradation of RRS1-R, independent of the presence of an integral PopP2 catalytic core. A liquid chromatography/tandem mass spectrometry analysis showed that PopP2 displays acetyl-transferase activity leading to its autoacetylation on a particular lysine residue, which is well conserved among all members of the YopJ family. These data suggest that this lysine residue may correspond to a key binding site for acetyl-coenzyme A required for protein activity. Indeed, mutation of this lysine in PopP2 abolishes RRS1-R-mediated immunity. In agreement with the guard hypothesis, our results favour the idea that activation of the plant immune response by RRS1-R depends not only on the physical interaction between the two proteins but also on its perception of PopP2 enzymatic activity.