Carbohydrate antigen 19-9 plus carcinoembryonic antigen for prognosis in colorectal cancer: An observational study.

AIM: Carcinoembryonic antigen (CEA) is a primary prognostic marker and can detect colorectal cancer (CRC) recurrence; however, it has low sensitivity. Carbohydrate antigen 19-9 (CA 19-9) can be used as a supplemental tumour marker along with CEA. The purpose of this study was to determine whether preoperative CA 19-9 added to CEA helped predict long-term prognosis and whether follow-up CA 19-9 added to CEA had additional benefits in diagnosing the recurrence of CRC. METHOD: We retrospectively assessed patients who underwent surgery for primary CRC between January 2004 and December 2015 at Seoul National University Hospital. Data on demographics, preoperative and follow-up CEA and CA 19-9 levels, recurrence and survival were obtained and analysed with respect to tumour marker levels to ascertain their prognostic and diagnostic values. RESULTS: A total of 4972 and 1530 patients were included to analyse preoperative and follow-up tumour marker levels, respectively. The 5-year relapse-free survival rates were 72.2% ± 0.8%, 52.5% ± 2.2%, 55.5% ± 3.2% and 32.1% ± 2.3% in the normal CEA and CA 19-9, high CEA, high CA 19-9, and high CEA and high CA 19-9 groups, respectively (all P < 0.001). Patients whose elevated CEA or CA 19-9 levels reduced to normal levels had better survival outcomes than those with postoperatively elevated levels. Elevated follow-up CA 19-9 and CEA levels were related to higher incidences of distant metastasis (CA 19-9, 14.0% vs. 23.1%, P = 0.004; CEA, 12.6% vs. 30.1%, P < 0.001) but not to local recurrence. Combined follow-up CEA and CA 19-9 increased the sensitivity for recurrence to 31.4%, with a 5% difference from the sensitivity of CEA alone. In the subgroup with high preoperative CA 19-9 levels, sensitivity increased by 18.2% overall. CONCLUSION: CA 19-9 is a valuable prognostic and diagnostic marker for CRC when used adjunctively with CEA and can be a supplementary marker with CEA to improve sensitivity, especially with elevated preoperative CA 19-9.

Triptycene-Fused Sterically Shielded Multi-Resonance TADF Emitter Enables High-Efficiency Deep Blue OLEDs with Reduced Dexter Energy Transfer.

Designing multi-resonance (MR) emitters that can simultaneously achieve narrowband emission and suppressed intermolecular interactions is challenging for realizing high color purity and stable blue organic light-emitting diodes (OLEDs). Herein, a sterically shielded yet extremely rigid emitter based on a triptycene-fused B,N core (Tp-DABNA) is proposed to address the issue. Tp-DABNA exhibits intense deep blue emissions with a narrow full width at half maximum (FWHM) and a high horizontal transition dipole ratio, superior to the well-known bulky emitter, t-DABNA. The rigid MR skeleton of Tp-DABNA suppresses structural relaxation in the excited state, with reduced contributions from the medium- and high-frequency vibrational modes to spectral broadening. The hyperfluorescence (HF) film composed of a sensitizer and Tp-DABNA shows reduced Dexter energy transfer compared to those of t-DABNA and DABNA-1. Notably, deep blue TADF-OLEDs with the Tp-DABNA emitter display higher external quantum efficiencies (EQEmax =24.8 %) and narrower FWHMs (≤26 nm) than t-DABNA-based OLEDs (EQEmax =19.8 %). The HF-OLEDs based on the Tp-DABNA emitter further demonstrate improved performance with an EQEmax of 28.7 % and mitigated efficiency roll-offs.

Boron-Based Multi-Resonance TADF Emitter with Suppressed Intermolecular Interaction and Isomer Formation for Efficient Pure Blue OLEDs.

Multi-resonance (MR) thermally activated delayed fluorescent (TADF) emitters are highly attractive due to their superior color purity as well as efficient light-harvesting ability from singlets and triplets. However, boron and nitrogen-based MR-TADF emitters suffer from their strong π-π interaction owing to their rigid flat cores. Herein, a boron-based multi-resonance blue TADF emitter with suppressed intermolecular interaction and isomer formation is developed through a simple synthetic process by introducing meta-xylene and meta-phenyphenyl groups to the core. The MR-TADF emitter, mBP-DABNA-Me, shows a narrowband blue emission with a peak at 467 nm, along with full width at half maximum of 28 nm, and photoluminescence quantum yield of 97%. Notably, highly efficient pure blue organic light-emitting diode (OLED) is realized using mBP-DABNA-Me, showing a maximum external quantum efficiency of 24.3% and a stable blue emission with a Commission Internationale de L'Eclairage coordinate of (0.124, 0.140). The color purity of the OLED is maintained at a high doping concentration of over 20%, attributed to the suppressed intermolecular interaction between the MR emitters.

The splicing factor 1-FLOWERING LOCUS M module spatially regulates temperature-dependent flowering by modulating FLOWERING LOCUS T and LEAFY expression.

KEY MESSAGE: The AtSF1-FLM module spatially controls temperature-dependent flowering by negatively regulating the expression of FT and LFY in the leaf and shoot apex, respectively. Alternative splicing mediated by various splicing factors is important for the regulation of plant growth and development. Our recent reports have shown that a temperature-dependent interaction between Arabidopsis thaliana splicing factor 1 (AtSF1) and FLOWERING LOCUS M (FLM) pre-mRNA introns controls the differential production of FLM-ß transcripts at different temperatures, eventually resulting in temperature-responsive flowering. However, the molecular and genetic interactions between the AtSF1-FLM module and floral activator genes remain unknown. Here, we aimed to identify the interactions among AtSF1, FLM, FLOWERING LOCUS T (FT), and LEAFY (LFY) by performing molecular and genetic analyses. FT and TWIN SISTER OF FT (TSF) expression in atsf1-2 mutants significantly increased in the morning and middle of the night at 16 and 23 °C, respectively, under long-day conditions. In addition, ft mutation suppressed the early flowering of atsf1-2 and atsf1-2 flm-3 mutants and masked the temperature response of atsf1-2 flm-3 mutants, suggesting that FT is a downstream target gene of the AtSF1-FLM module. LFY expression significantly increased in the diurnal samples of atsf1-2 mutants and in the shoot apex regions of atsf1-2 ft-10 mutants at different temperatures. The chromatin immunoprecipitation (ChIP) assay revealed that FLM directly binds to the genomic regions of LFY but not of APETALA1 (AP1). Moreover, lfy mutation suppressed the early flowering of flm-3 mutants, suggesting that LFY is another target of the AtSF1-FLM module. Our results reveal that the AtSF1-FLM module spatially modulates temperature-dependent flowering by regulating FT and LFY expressions.

The progression of the vertebral body bruise associated with a spinal fracture.

BACKGROUND: Advances in magnetic resonance imaging (MRI) have made it possible to find the vertebral body bruise (VBB), which was not found in computed tomography (CT) after trauma. There has been only one study with adult patients about whether traumatic VBB will cause a collapse of the vertebral body or not. The purpose is to elucidate the progression of VBB in non-osteoporotic adult patients and to identify the possible factors influencing the progression. METHOD: The VBB was defined on MRI as band-like or diffuse zones of high signal intensity on T2-weighted sequences without fracture of the cortex based on CT. The study population with traumatic VBB associated with non-osteoporotic spinal fracture was composed of 15 females and 21 males. The minimal follow-up period was 6 months. The ratio of anterior to posterior heights of the VBB, the ratio of anterior heights of the VBB to the average of those of cranial and caudal adjacent vertebral bodies, the anterior wedge angle of the VBB, and the focal angle around the VBB were compared between the initial and final visits. We evaluated the age of the patients, the C2 plumb line distance, the regional location of VBB, the etiology of VBB, and the treatment methods of the fractures as possible risk factors influencing the progression. RESULTS: There was no difference in the ratios and angles between the initial and final visits. The differences in the ratios and angles between the initial and final visits were not dependent on the possible risk factors. The anterior superior area is the most common in the distribution of VBB. CONCLUSIONS: Unlike compression fractures, the vertebral body with traumatic VBB found in adult patients with non-osteoporotic spinal fractures of AO classification A or B types did not develop collapse. In clinical practice, it is reasonable to diagnose it as a spinal fracture rather than a VBB if the collapse of a possible VBB occurs.

An Aluminosilicate Zeolite Containing Rings of Tetrahedral Atoms with All Odd Numbers from Five to Eleven.

Herein we report the synthesis, structure solution, and catalytic properties of PST-31, which has an unprecedented framework topology. This high-silica (Si/Al=16) zeolite was synthesized using a pyrazolium-based dication with a tetramethylene linker as an organic structure-directing agent (OSDA) in hydroxide media. The PST-31 structure is built from new building layers containing four-, five-, six-, and seven-membered rings, which are connected by single four-membered rings in the interlayer region to form a two-dimensional pore system. Its channels consist of [4.56 .6.9.11] and [5.6.7.9.10.11] cavities and are thus delimited by nine-, ten-, and eleven-membered rings. The OSDA cations in as-synthesized PST-31 were determined to reside without disorder in the large [42 .514 .64 .72 .94 ] cavities composed of smaller [4.56 .6.9.11] and [5.6.7.9.10.11] ones, leading to a symmetry coincidence between the OSDA and the surrounding zeolite cavity. The proton form of PST-31 was found to be selective for the cracking of n-hexane to light olefins.

What Is the Effect of the Ulnar-Plus Variance on the Outcomes of Arthroscopic Repair of the Peripheral Ulnar-Side Triangular Fibrocartilage Complex Tear?

PURPOSE: To compare the outcomes of arthroscopic repair of peripheral ulnar-side triangular fibrocartilage complex (TFCC) tears between patients with and without ulnar-plus variance (UPV) and to identify factors associated with index surgery failure in these patients. METHODS: We retrospectively analyzed 50 consecutive patients who underwent arthroscopic repair of peripheral ulnar-side TFCC tears from June 2014 to February 2018. We selected patients who were aged at least 18 years and underwent arthroscopic repair of peripheral ulnar-side TFCC tears. We excluded those with a fractured or dislocated wrist, ulnar impaction syndrome, degenerative or inflammatory arthritis of the wrist, or neurologic conditions that affect upper-extremity function, as well as those who received less than 12 months' follow-up. We evaluated the patients with a visual analog scale for pain in 3 domains (overall, with hard work, and at rest), the Patient-rated Wrist Evaluation, range of motion, and grip strength. Clinical outcomes and arthroscopic findings were compared between patients with and without UPV (UPV group and non-UPV group, respectively). We calculated the relative risk and 95% confidence interval for younger age (<30 years), sex, UPV, and coexisting degenerative central TFCC tear (type 2 tear) to determine the risk factors for arthroscopic repair failure. RESULTS: No significant differences were noted between the 2 groups regarding visual analog scale pain and Patient-rated Wrist Evaluation scores and rates of excellent or improved outcomes (P > .05). Arthroscopic repair failure was found in 4 patients. A coexisting type 2 TFCC tear was the only significant risk factor (relative risk, 49.5; 95% confidence interval, 2.94-83.96; P = .007) for arthroscopic repair failure. CONCLUSIONS: UPV did not significantly affect the outcomes of arthroscopic repair of peripheral ulnar-side TFCC tears. However, coexisting type 2 TFCC tears significantly increased the risk of index surgery failure in these patients. LEVEL OF EVIDENCE: Level IV, prognostic study.

Evaluation of Joint Motion Sensing Efficiency According to the Implementation Method of SWCNT-Coated Fabric Motion Sensor.

The purpose of this study was to investigate the effects of the shape and attachment position of stretchable textile piezoresistive sensors coated with single-walled carbon nanotubes on their performance in measuring the joint movements of children. The requirements for fabric motion sensors suitable for children are also identified. The child subjects were instructed to wear integrated clothing with sensors of different shapes (rectangular and boat-shaped), attachment positions (at the knee and elbow joints or 4 cm below the joints). The change in voltage caused by the elongation and contraction of the fabric sensors was measured for the flexion-extension motions of the arms and legs at 60°/s (three measurements of 10 repetitions each for the 60° and 90° angles, for a total of 60 repetitions). Their reliability was verified by analyzing the agreement between the fabric motion sensors and attached acceleration sensors. The experimental results showed that the fabric motion sensor that can measure children's arm and leg motions most effectively is the rectangular-shaped sensor attached 4 cm below the joint. In this study, we developed a textile piezoresistive sensor suitable for measuring the joint motion of children, and analyzed the shape and attachment position of the sensor on clothing suitable for motion sensing. We showed that it is possible to sense joint motions of the human body by using flexible fabric sensors integrated into clothing.

Expression and In Vitro Function of Anti-Breast Cancer Llama-Based Single Domain Antibody VHH Expressed in Tobacco Plants.

Overexpression of human epidermal growth factor receptor type 2 (HER2) is considered as a prognostic factor of breast cancer, which is positively associated with recurrence when cancer metastasizes to the lymph nodes. Here, we expressed the single variable domain on a heavy chain (VHH) form of anti-HER2 camelid single domain antibody in tobacco plants and compared its in vitro anticancer activities with the anti-HER2 full size antibody. The gene expression cassette containing anti-HER2 camelid single domain antibody VHH fused to human IgG Fc region with KDEL endoplasmic reticulum (ER) (VHH-FcK) was transferred into the tobacco plant via the Agrobacterium-mediated transformation. The transformants were screened with polymerase chain reaction and Western blot analyses. Enzyme-linked immunosorbent assay (ELISA) confirmed the binding of the purified anti-HER2 VHH-FcK to the HER2-positive breast cancer cell line, SK-BR-3. Migration assay results confirmed anticancer activity of the plant-derived anticancer camelid single chain antibody. Taken together, we confirmed the possibility of using anti-HER2 VHH-FcK as a therapeutic anticancer agent, which can be expressed and assembled and purified from a plant expression system as an alternative antibody production system.

PST-24: A Zeolite with Varying Intracrystalline Channel Dimensionality.

Herein we report the synthesis, structure solution, and catalytic properties of PST-24, a novel channel-based medium-pore zeolite. This zeolite was synthesized via the excess fluoride approach. Electron diffraction shows that its structure is built by composite cas-zigzag (cas-zz) building chains, which are connected by double 5-ring (d5r) columns. While the cas-zz building chains are ordered in the PST-24 framework, the d5r columns adopt one of two possible arrangements; the two adjacent d5r columns are either at the same height or at different heights, denoted arrangements S and D, which can be regarded as open and closed valves that connect the channels, respectively. A framework with arrangement D only has a 2D 10-ring channel system, whereas that with arrangement S only contains 3D channels. In actual PST-24 crystals, the open and closed valves are almost randomly dispersed to yield a zeolite framework where the channel dimensionality varies locally from 2D to 3D.

Perovskite Light-Emitting Diodes with Improved Outcoupling Using a High-Index Contrast Nanoarray.

Organic-inorganic hybrid perovskite light-emitting diodes (PeLEDs) are promising for next-generation optoelectronic devices due to their potential to achieve high color purity, efficiency, and brightness. Although the external quantum efficiency (EQE) of PeLEDs has recently surpassed 20%, various strategies are being pursued to increase EQE further and reduce the EQE gap compared to other LED technologies. A key point to further boost EQE of PeLEDs is linked to the high refractive index of the perovskite emissive layer, leading to optical losses of more than 70% of emitted photons. Here, it is demonstrated that a randomly distributed nanohole array with high-index contrast can effectively enhance outcoupling efficiency in PeLEDs. Based on a comprehensive optical analysis on the perovskite thin film and outcoupling structure, it is confirmed that the nanohole array effectively distributes light into the substrate for improved outcoupling, allowing for 1.64 times higher light extraction. As a result, highly efficient red/near-infrared PeLEDs with a peak EQE of 14.6% are demonstrated.

Natural History of Gastric Cancer: Observational Study of Gastric Cancer Patients Not Treated During Follow-Up.

BACKGROUND: Understanding the natural progression of untreated gastric cancer is critical for determining the disease prognosis as well as treatment options and timing. The aim of this study is to analyze the natural history of gastric cancer. PATIENTS AND METHODS: We included patients with gastric cancer who had not received any treatment and were staged using endoscopy/endoscopic ultrasonography and computed tomography on at least two follow-up visits during intervals of nontreatment. Tumor volumes were also measured in addition to the staging. Survival of each stage at diagnosis was also analyzed. RESULTS: A total of 101 patients were included. The mean follow-up period was 35.1 ± 34.4 months. The gastric cancer doubling time was 11.8 months for T1 and 6.2 months for T4. The progression time from early gastric cancer to advanced gastric cancer was 34 months. It decreased as the stages advanced: from 34 months between tumor-nodes-metastasis stage I and II to 1.8 months between stage III and IV. No variable was identified as a risk factor for cancer progression. The 5-year survival rates of untreated patients were 46.2% in stage I and 0% in stage II, stage III, and stage IV. CONCLUSIONS: The progression and doubling times of gastric cancer shorten as the stages advance. Objective data reported in this study can be a critical factor in determining treatment timing and screening interval.

Identification of quantitative trait loci governing subgynoecy in cucumber.

KEY MESSAGE: QTL-seq analysis identified three major QTLs conferring subgynoecy in cucumbers. Furthermore, sequence and expression analyses predicted candidate genes controlling subgynoecy. The cucumber (Cucumis sativus L.) is a typical monoecious having individual male and female flowers, and sex differentiation is an important developmental process that directly affects its fruit yield. Subgynoecy represents a sex form with a high degree of femaleness and would have alternative use as gynoecy under limited resource conditions. Recently, many studies have been reported that QTL-seq, which integrates the advantages of bulked segregant analysis and high-throughput whole-genome resequencing, can be a rapid and cost-effective way of mapping QTLs. Segregation analysis in the F2 and BC1 populations derived from a cross between subgynoecious LOSUAS and monoecious BMB suggested the quantitative nature of subgynoecy in cucumbers. Both genome-wide SNP profiling of subgynoecious and monoecious bulks constructed from F2 and BC1 plants consistently identified three significant genomic regions, one on chromosome 3 (sg3.1) and another two on short and long arms of chromosome 1 (sg1.1 and sg1.2). Classical QTL analysis using the F2 confirmed sg3.1 (R2 = 42%), sg1.1 (R2 = 29%) and sg1.2 (R2 = 18%) as major QTLs. These results revealed the unique genetic inheritance of subgynoecious line LOSUAS through two distinct major QTLs, sg3.1 and sg1.1, which mainly increase degree of femaleness, while another QTL, sg1.2, contributes to decrease it. This study demonstrated that QTL-seq allows rapid and powerful detection of QTLs using preliminary generation mapping populations such as F2 or BC1 population and further that the identified QTLs could be useful for molecular breeding of cucumber lines with high yield potential.

The overexpression of cucumber (Cucumis sativus L.) genes that encode the branched-chain amino acid transferase modulate flowering time in Arabidopsis thaliana.

KEY MESSAGE: The overexpression of CsBCATs promotes flowering in Arabidopsis by regulating the expression of flowering time genes. The branched-chain amino acid transferases (BCATs) play an important role in the metabolism of branched-chain amino acids (BCAAs), such as isoleucine, leucine, and valine. They function in both the synthesis and the degradation of this class of amino acids. We identified and characterized the three BCAT genes in cucumber (Cucumis sativus L.). The tissue-specific expression profiling in cucumber plants revealed that CsBCAT2 and CsBCAT7 were highly expressed in the reproductive tissues, whereas CsBCAT3 expression was highly detected in the vegetative tissues. The subcellular localization patterns of three CsBCATs were observed in the mitochondria. The functional analyses of CsBCATs showed that CsBCAT2 and CsBCAT3 restored the growth of bat1Δ/bat2Δ double knockout yeast (Saccharomyces cerevisiae), and CsBCAT3 and CsBCAT7 with different substrate preferences acted in a reverse reaction. The transgenic approach demonstrated that the overexpression of the three CsBCATs resulted in early flowering phenotypes, which were associated with the upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) in a manner in which they were dependent on GIGANTEA (GI)/CONSTANS (CO) and SHORT VEGETATIVE PHASE (SVP)/FLOWERING LOCUS C (FLC) modules. Our results, which are observed in conjunction, suggest that there is an interconnection between BCAT genes that function in BCAA metabolism and the flowering time in plants.

Optimal Nitrogen Incorporation in Nickel Silicide for Thermally Stable Contact Formation.

Nickel silicide (NiSi) is commonly used as a contact material for metal junctions but the poor thermal instability of NiSi above 600 °C has limited the further scaling down of devices and the implementation of novel schemes, such as monolithic 3-dimensional integration. This paper suggests a process to improve the thermal stability of NiSi through nitrogen incorporation during the silicidation process. The optimal level of nitrogen incorporation in NiSi reduced the nickel diffusion rate and enhanced the thermal stability by preventing the formation of a nickel disilicide phase. On the other hand, a higher level of N incorporation led to Ni3N formation, which impeded the complete transformation to NiSi. Therefore, it is essential to incorporate the optimal content of N. In this study, NiSi with 3.9% N incorporation showed superior electrical characteristics, such as the sheet resistance, junction leakage, and stable Schottky barrier height, even after high-temperature post silicidation annealing at 600 °C for 30 min.

Combined Alkali-Organoammonium Structure Direction of High-Charge-Density Heteroatom-Containing Aluminophosphate Molecular Sieves.

The charge density mismatch concept was applied to the synthesis of high-charge-density silicoaluminophosphate SAPO-69 (OFF) and SAPO-79 (ERI) and zincoaluminophosphate PST-16 (CGS), PST-17 (BPH), PST-19 (SBS), and ZnAPO-88 (MER) molecular sieves. Combined alkali-organoammonium structure direction in these systems is thus enabled. Structure direction is treated from the perspective of stabilizing an ionic framework, the relationships between reaction charge density (OH- /H3 PO4 ), alkali and organoammonium content, and ionicity of tetrahedral framework atoms in successful structure direction are presented.

Abnormal elastic modulus behavior in a crystalline-amorphous core-shell nanowire system.

We investigated the elastic modulus behavior of crystalline InAs/amorphous Al2O3 core-shell heterostructured nanowires with shell thicknesses varying between 10 and 90 nm by conducting in situ tensile tests inside a transmission electron microscope (TEM). Counterintuitively, the elastic modulus behaviors of InAs/Al2O3 core-shell nanowires differ greatly from those of bulk-scale composite materials, free from size effects. According to our results, the elastic modulus of InAs/Al2O3 core-shell nanowires increases, peaking at a shell thickness of 40 nm, and then decreases in the range of 50-90 nm. This abnormal behavior is attributed to the continuous decrease in the elastic modulus of the Al2O3 shell as the thickness increases, which is caused by changes in the atomic/electronic structure during the atomic layer deposition process and the relaxation of residual stress/strain in the shell transferred from the interfacial mismatch between the core and shell materials. A novel method for estimating the elastic modulus of the shell in a heterostructured core-shell system was suggested by considering these two effects, and the predictions from the suggested method coincided well with the experimental results. We also found that the former and latter effects account for 89% and 11% of the change in the elastic modulus of the shell. This study provides new insight by showing that the size dependency, which is caused by the inhomogeneity of the atomic/electronic structure and the residual stress/strain, must be considered to evaluate the mechanical properties of heterostructured nanowires.

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms.

KEY MESSAGE: The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion. The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3' splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins' Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.

RRM domain of Arabidopsis splicing factor SF1 is important for pre-mRNA splicing of a specific set of genes.

KEY MESSAGE: The RNA recognition motif of Arabidopsis splicing factor SF1 affects the alternative splicing of FLOWERING LOCUS M pre-mRNA and a heat shock transcription factor HsfA2 pre-mRNA. Splicing factor 1 (SF1) plays a crucial role in 3' splice site recognition by binding directly to the intron branch point. Although plant SF1 proteins possess an RNA recognition motif (RRM) domain that is absent in its fungal and metazoan counterparts, the role of the RRM domain in SF1 function has not been characterized. Here, we show that the RRM domain differentially affects the full function of the Arabidopsis thaliana AtSF1 protein under different experimental conditions. For example, the deletion of RRM domain influences AtSF1-mediated control of flowering time, but not the abscisic acid sensitivity response during seed germination. The alternative splicing of FLOWERING LOCUS M (FLM) pre-mRNA is involved in flowering time control. We found that the RRM domain of AtSF1 protein alters the production of alternatively spliced FLM-ß transcripts. We also found that the RRM domain affects the alternative splicing of a heat shock transcription factor HsfA2 pre-mRNA, thereby mediating the heat stress response. Taken together, our results suggest the importance of RRM domain for AtSF1-mediated alternative splicing of a subset of genes involved in the regulation of flowering and adaptation to heat stress.