Plants adapt their growth and development in response to perceived salt stress. Although DELLA-dependent growth restraint is thought to be an integration of the plant's response to salt stress, little is known about how histone modification confers salt stress and, in turn, affects development. Here, we report that floral initiator Shk1 kinase binding protein1 (SKB1) and histone4 arginine3 (H4R3) symmetric dimethylation (H4R3sme2) integrate responses to plant developmental progress and salt stress. Mutation of SKB1 results in salt hypersensitivity, late flowering, and growth retardation. SKB1 associates with chromatin and thereby increases the H4R3sme2 level to suppress the transcription of FLOWERING LOCUS C (FLC) and a number of stress-responsive genes. During salt stress, the H4R3sme2 level is reduced, as a consequence of SKB1 disassociating from chromatin to induce the expression of FLC and the stress-responsive genes but increasing the methylation of small nuclear ribonucleoprotein Sm-like4 (LSM4). Splicing defects are observed in the skb1 and lsm4 mutants, which are sensitive to salt. We propose that SKB1 mediates plant development and the salt response by altering the methylation status of H4R3sme2 and LSM4 and linking transcription to pre-mRNA splicing.

Purpose To prospectively assess agreement and repeatability of magnetic resonance (MR) elastography liver stiffness measurements across imager manufacturers, field strengths, and pulse sequences. Materials and Methods This prospective cross-sectional study was approved by the institutional review board; informed consent was obtained from all subjects. On the basis of an a priori power calculation, 24 volunteer adult subjects underwent MR elastography with four MR imaging systems (two vendors) and multiple pulse sequences (two-dimensional [2D] gradient-echo [GRE] imaging, 2D spin-echo [SE] echo-planar imaging, and three-dimensional [3D] SE echo-planar imaging). Each sequence was performed twice in each patient with each imaging system. Intraclass correlation coefficients (ICCs) were used to assess agreement and repeatability. P < .05 was considered indicative of a statistically significant difference. Results Pairwise ICCs were 0.67-0.82 and 0.62-0.83 for agreement between pulse sequences across manufacturers (n = 4) and field strengths (n = 5), respectively. ICCs were 0.45-0.90 for pairwise agreement between sequences while fixing manufacturer and field strength (n = 8). Test-retest repeatability across the various manufacturer, field strength, and pulse sequence combinations (n = 10) was excellent (ICCs, 0.77-0.94). The overall ICC for all manufacturer, field strength, and sequence combinations (n = 10) was 0.68 (95% confidence interval [CI]: 0.55, 0.82). ICC according to field strength was 0.78 (95% CI: 0.67, 0.88) at 1.5 T (n = 5) and 0.64 (95% CI: 0.49, 0.78) at 3.0 T (n = 5). ICCs according to vendor were 0.83 (95% CI: 0.73, 0.91) (n = 4) and 0.65 (95% CI: 0.51, 0.79) (n = 6). Average patient level variance was 0.042 kPa, with a coefficient of variation of 10.7%. Conclusion MR elastography is a reliable method for assessing liver stiffness, with small amounts of variability between imager manufacturers, field strengths, and pulse sequences. RSNA, 2016.

Snapdragon (Antirrhinum majus L.), a member of the Plantaginaceae family, is an important model for plant genetics and molecular studies on plant growth and development, transposon biology and self-incompatibility. Here we report a near-complete genome assembly of A. majus cultivar JI7 (A. majus cv.JI7) comprising 510 Megabases (Mb) of genomic sequence and containing 37,714 annotated protein-coding genes. Scaffolds covering 97.12% of the assembled genome were anchored on eight chromosomes. Comparative and evolutionary analyses revealed that a whole-genome duplication event occurred in the Plantaginaceae around 46–49 million years ago (Ma). We also uncovered the genetic architectures associated with complex traits such as flower asymmetry and self-incompatibility, identifying a unique duplication of TCP family genes dated to around 46–49 Ma and reconstructing a near-complete ψS-locus of roughly 2 Mb. The genome sequence obtained in this study not only provides a representative genome sequenced from the Plantaginaceae but also brings the popular plant model system of Antirrhinum into the genomic age.

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The dynamic chromatin activities of Mi-2/Nucleosome Remodeling and Histone deacetylation (Mi-2/NuRD) complexes in mammals are at the basis of current research on stemness, longevity/ageing, and cancer (4-2-1/SLAC), and have been widely studied over the past decade in mammals and the elegant model organism, Caenorhabditis elegans. Interestingly, a common emergent theme from these studies is that of distinct coregulator-recruited Mi-2/NuRD complexes largely orchestrating the 4-2-1/SLAC within a unique paradigm by maintaining genome stability via DNA repair and controlling three types of transcriptional programs in concert in a number of cellular, tissue, and organism contexts. Thus, the core Mi-2/NuRD complex plays a central role in 4-2-1/SLAC. The plasticity and robustness of 4-2-1/SLAC can be interpreted as modulation of specific coregulator(s) within cell-specific, tissue-specific, stage-specific, or organism-specific niches during stress induction, ie, a functional module and its networking, thereby conferring differential responses to different environmental cues. According to “Occam’s razor”, a simple theory is preferable to a complex one, so this simplified notion might be useful for exploring 4-2-1/SLAC with a holistic view. This thought could also be valuable in forming strategies for future research, and could open up avenues for cancer prevention and antiageing strategies.

Sugar transporter proteins (STPs), such as H+/sugar symporters, play essential roles in plants’ sugar transport, growth, and development, and possess an important potential to enhance plants’ performance of multiple agronomic traits, especially crop yield and stress tolerance. However, the evolutionary dynamics of this important gene family in Gramineae crops are still not well-documented and functional differentiation of rice STP genes remain unclear. To address this gap, we conducted a comparative genomic study of STP genes in seven representative Gramineae crops, which are Brachypodium distachyon (Bd), Hordeum vulgare (Hv), Setaria italica (Si), Sorghum bicolor (Sb), Zea mays (Zm), Oryza rufipogon (Or), and Oryza sativa ssp. japonica (Os). In this case, a total of 177 STP genes were identified and grouped into four clades. Of four clades, the Clade I, Clade III, and Clade IV showed an observable number expansion compared to Clade II. Our results of identified duplication events and divergence time of duplicate gene pairs indicated that tandem, Whole genome duplication (WGD)/segmental duplication events play crucial roles in the STP gene family expansion of some Gramineae crops (expect for Hv) during a long-term evolutionary process. However, expansion mechanisms of the STP gene family among the tested species were different. Further selective force studies revealed that the STP gene family in Gramineae crops was under purifying selective forces and different clades and orthologous groups with different selective forces. Furthermore, expression analysis showed that rice STP genes play important roles not only in flower organs development but also under various abiotic stresses (cold, high-temperature, and submergence stresses), blast infection, and wounding. The current study highlighted the expansion and evolutionary patterns of the STP gene family in Gramineae genomes and provided some important messages for the future functional analysis of Gramineae crop STP genes.

Background Cell division cycle associated 2 (CDCA2), upregulated in lung adenocarcinoma and oral squamous cell carcinoma, may be related to some malignant diseases. Nevertheless, its role in colorectal cancer (CRC) remains unknown. Methods CDCA2 expression was analyzed using The Cancer Genome Atlas (TCGA), quantitative real-time PCR (qRT-PCR), and immunohistochemistry. The impact of CDCA2 on cell proliferation was analyzed via loss- or gain-of-function assays. Furthermore, gene set enrichment analysis was conducted to explore the potential mechanism of CDCA2 in CRC. Lastly, the expression levels of CCND1 and AKT were measured in CRC cell lines. Results Our study revealed that CDCA2 expression was associated with tumor progression. Through loss- or gain-of-function assays, we found that upregulation of CDCA2 promoted the proliferation of DLD-1 cells, however, downregulation of CDCA2 in SW480 cells restrained proliferative capacity both in vitro and in vivo . The results of flow cytometry showed that CDCA2 promoted cell cycle progression via upregulation of CCND1 in CRC cell lines. In the following experiments, we found that CDCA2 regulated CCND1 expression through activating the PI3K/AKT pathway, and confirmed this using a specific PI3K inhibitor (LY294002). Conclusions This study demonstrates that overexpression of CDCA2 might target CCND1 to promote CRC cell proliferation and tumorigenesis through activation of the PI3K/AKT pathway.

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