CAR modulates plasma membrane nano-organization and immune signaling downstream of RALF1-FERONIA signaling pathway.

In Arabidopsis, the receptor-like kinase (RLK) FERONIA (FER) senses peptide ligands in the plasma membrane (PM), modulates plant growth and development, and integrates biotic and abiotic stress signaling for downstream adaptive responses. However, the molecular interplay of these diverse processes is largely unknown. Here, we show that FER, the receptor of Rapid Alkalinization Factor 1 (RALF1), physically interacts with C2 domain ABA-related (CAR) proteins to control the nano-organization of the PM. During this process, the RALF1-FER pathway upregulates CAR protein translation, and then more CAR proteins are recruited to the PM. This acts as a rapid feedforward loop that stabilizes the PM liquid-ordered phase. FER interacts with and phosphorylates CARs, thereby reducing their lipid-binding ability and breaking the feedback regulation at later time points. The formation of the flg22-induced FLS2-BAK1 immune complex, which depends on the integrity of FER-containing nanodomains, is impaired in fer and pentuple car14569 mutant. Together, we propose that the FER-CAR module controls the formation of PM nano-organization during RALF signaling through a self-contained amplifying loop including both positive and negative feedback.

OsSRK1, a lectin receptor-like kinase, controls plant height by mediating internode elongation in Oryza sativa L.

LecRLKs (lectin receptor-like kinases) is a subfamily of RLKs (receptor like kinase) and takes part in mounds of biological processes in plant-environment interaction. However, the roles of LecRLKs in plant development are still elusive. Here, we showed that OsSRK1, belonging to LecRLK family in rice, had a relative higher expression in internode and stem in comparison with that in root and leaf. Importantly, srk1-1 and srk1-2, two genome-edited mutants of OsSRK1 using CRISPR/Cas9 system, exhibited obviously a decreased plant height and shorter length of the first internode and second internode compared with those in WT. Subsequently, histochemical sectioning showed that the stem diameter and the cell length in stem are significantly reduced in srk1-1 and srk1-2 compared with WT. Moreover, analyzing the expression of four gibberellin biosynthesis related genes showed that CPS, KAO, KS1, and GA3ox2 expression had similar levels between WT and mutants. Importantly, we further verified that OsSRK1 can directly interact with gibberellin receptor GID1. Together, our results revealed that LecRLKs family member OsSRK1 positively regulated plant height by controlling internode elongation which maybe depended on OsSRK1-GID1 interaction mediated gibberellin signaling transduction. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01340-6.

EBP1 nuclear accumulation negatively feeds back on FERONIA-mediated RALF1 signaling.

FERONIA (FER), a plasma membrane receptor-like kinase, is a central regulator of cell growth that integrates environmental and endogenous signals. A peptide ligand rapid alkalinization factor 1 (RALF1) binds to FER and triggers a series of downstream events, including inhibition of Arabidopsis H+-ATPase 2 activity at the cell surface and regulation of gene expression in the nucleus. We report here that, upon RALF1 binding, FER first promotes ErbB3-binding protein 1 (EBP1) mRNA translation and then interacts with and phosphorylates the EBP1 protein, leading to EBP1 accumulation in the nucleus. There, EBP1 associates with the promoters of previously identified RALF1-regulated genes, such as CML38, and regulates gene transcription in response to RALF1 signaling. EBP1 appears to inhibit the RALF1 peptide response, thus forming a transcription-translation feedback loop (TTFL) similar to that found in circadian rhythm control. The plant RALF1-FER-EBP1 axis is reminiscent of animal epidermal growth factor receptor (EGFR) signaling, in which EGF peptide induces EGFR to interact with and phosphorylate EBP1, promoting EBP1 nuclear accumulation to control cell growth. Thus, we suggest that in response to peptide signals, plant FER and animal EGFR use the conserved key regulator EBP1 to control cell growth in the nucleus.

TMK4 receptor kinase negatively modulates ABA signaling by phosphorylating ABI2 and enhancing its activity.

In plants, clade A type 2C protein phosphatases (PP2CAs) have emerged as major players in abscisic acid (ABA)-regulated stress responses by inhibiting protein kinase activity. However, how different internal and external environmental signals modulate the activity of PP2CAs are not well known. The transmembrane kinase (TMK) protein 4 (TMK4), one member of a previously identified receptor kinase subfamily on the plasma membrane that plays vital roles in plant cell growth, directly interacts with PP2CAs member (ABA-Insensitive 2, ABI2). tmk4 mutant is hypersensitive to ABA in both ABA-inhibited seed germination and primary root growth, indicating that TMK4 is a negative regulator in ABA signaling pathway. Further analyses indicate that TMK4 phosphorylates ABI2 at three conserved Ser residues, thus enhancing the activity of ABI2. The phosphorylation-mimic ABI2S139DS140DS266D can complement but non-phosphorylated form ABI2S139AS140AS266A cannot complement ABA hypersensitive phenotype of the loss-of-function mutant abi1-2abi2-2. This study provides a previously unidentified mechanism for positively regulating ABI2 by a plasma membrane protein kinase.

Arabidopsis RAD23B regulates pollen development by mediating degradation of KRP1.

The ubiquitin (Ub)/26S proteasome system (UPS) plays a key role in plant growth, development, and survival by directing the turnover of numerous regulatory proteins. In the UPS, the ubiquitin-like (UBL) and ubiquitin-associated (UBA) domains function as hubs for ubiquitin-mediated protein degradation. Radiation sensitive 23 (RAD23), which has been identified as a UBL/UBA protein, contributes to the progression of the cell cycle, stress responses, ER proteolysis, and DNA repair. Here, we report that pollen development is arrested at the microspore stage in a rad23b null mutant. We demonstrate that RAD23B can directly interact with KIP-related protein 1 (KRP1) through its UBL-UBA domains. In addition, plants overexpressing KRP1 have defects in pollen development, which is a phenotype similar to the rad23b mutant. RAD23B promotes the degradation of KRP1 in vivo, which is accumulated following treatment with the proteasome inhibitor MG132. Our results indicate that RAD23B plays an important in pollen development by controlling the turnover of the key cell cycle protein, KRP1.

Effects of Edaravone on Neurological Function and Tumor Necrosis Factor Alpha and Interleukin 8 Levels in Patients with Cerebral Infarction.

OBJECTIVE: The present study aimed to explore the effects of edaravone on neurological function, tumor necrosis factor α (TNF-α), and interleukin (IL)-8 levels in patients with cerebral infarction. METHODS: A total of 96 patients with cerebral -infarction who were admitted to the department of neurology in our hospital were enrolled in the present study, and they were randomly assigned to Group A (n = 48) and Group B (n = 48). Group A was treated with conventional therapy plus edaravone for 2 weeks and Group B with conventional therapy alone for 2 weeks. Enzyme-linked immunosorbent assay was used to determine serum TNF-α and IL-8 levels before and after treatment, and Pearson correlation analysis was conducted to analyze the correlation between serum TNF-α and IL-8 levels as well as National Institutes of Health Stroke Scale (NIHSS) score. RESULTS: After treatment, Group A had a lower NIHSS score and serum TNF-α and IL-8 levels as well as higher activities of daily living score than Group B (all p < 0.05). In addition, after treatment, no significant differences were observed between the 2 groups in terms of the presence of adverse reactions (p > 0.05). Pearson correlation analysis revealed a significant positive correlation between serum TNF-α and IL-8 levels as well as NIHSS score (r = -0.567 and r = -0.556, both p < 0.05). CONCLUSION: Edaravone can improve the neurological function of patients without causing evident adverse reactions, thereby improving quality of life, which may be correlated to decreased serum TNF-α and IL-8 levels.

Receptor kinase complex transmits RALF peptide signal to inhibit root growth in Arabidopsis.

A number of hormones work together to control plant cell growth. Rapid Alkalinization Factor 1 (RALF1), a plant-derived small regulatory peptide, inhibits cell elongation through suppression of rhizosphere acidification in plants. Although a receptor-like kinase, FERONIA (FER), has been shown to act as a receptor for RALF1, the signaling mechanism remains unknown. In this study, we identified a receptor-like cytoplasmic kinase (RPM1-induced protein kinase, RIPK), a plasma membrane-associated member of the RLCK-VII subfamily, that is recruited to the receptor complex through interacting with FER in response to RALF1. RALF1 triggers the phosphorylation of both FER and RIPK in a mutually dependent manner. Genetic analysis of the fer-4 and ripk mutants reveals RIPK, as well as FER, to be required for RALF1 response in roots. The RALF1-FER-RIPK interactions may thus represent a mechanism for peptide signaling in plants.

FERONIA interacts with ABI2-type phosphatases to facilitate signaling cross-talk between abscisic acid and RALF peptide in Arabidopsis.

Receptor-like kinase FERONIA (FER) plays a crucial role in plant response to small molecule hormones [e.g., auxin and abscisic acid (ABA)] and peptide signals [e.g., rapid alkalinization factor (RALF)]. It remains unknown how FER integrates these different signaling events in the control of cell growth and stress responses. Under stress conditions, increased levels of ABA will inhibit cell elongation in the roots. In our previous work, we have shown that FER, through activation of the guanine nucleotide exchange factor 1 (GEF1)/4/10-Rho of Plant 11 (ROP11) pathway, enhances the activity of the phosphatase ABA Insensitive 2 (ABI2), a negative regulator of ABA signaling, thereby inhibiting ABA response. In this study, we found that both RALF and ABA activated FER by increasing the phosphorylation level of FER. The FER loss-of-function mutant displayed strong hypersensitivity to both ABA and abiotic stresses such as salt and cold conditions, indicating that FER plays a key role in ABA and stress responses. We further showed that ABI2 directly interacted with and dephosphorylated FER, leading to inhibition of FER activity. Several other ABI2-like phosphatases also function in this pathway, and ABA-dependent FER activation required PYRABACTIN RESISTANCE (PYR)/PYR1-LIKE (PYL)/REGULATORY COMPONENTS OF ABA RECEPTORS (RCAR)-A-type protein phosphatase type 2C (PP2CA) modules. Furthermore, suppression of RALF1 gene expression, similar to disruption of the FER gene, rendered plants hypersensitive to ABA. These results formulated a mechanism for ABA activation of FER and for cross-talk between ABA and peptide hormone RALF in the control of plant growth and responses to stress signals.

TMK4-mediated FIP37 phosphorylation regulates auxin-triggered N6-methyladenosine modification of auxin biosynthetic genes in Arabidopsis.

The dynamics of N6-methyladenosine (m6A) mRNA modification are tightly controlled by the m6A methyltransferase complex and demethylases. Here, we find that auxin treatment alters m6A modification on auxin-responsive genes. Mechanically, TRANSMEMBRANE KINASE 4 (TMK4), a component of the auxin signaling pathway, interacts with and phosphorylates FKBP12-INTERACTING PROTEIN 37 (FIP37), a core component of the m6A methyltransferase complex, in an auxin-dependent manner. Phosphorylation of FIP37 enhances its interaction with RNA, thereby increasing m6A modification on its target genes, such as NITRILASE 1 (NIT1), a gene involved in indole-3-acetic acid (IAA) biosynthesis. 1-Naphthalacetic acid (NAA) treatment accelerates the mRNA decay of NIT1, in a TMK4- and FIP37-dependent manner, which leads to inhibition of auxin biosynthesis. Our findings identify a regulatory mechanism by which auxin modulates m6A modification through the phosphorylation of FIP37, ultimately affecting mRNA stability and auxin biosynthesis in plants.

Molecular character of a phosphatase 2C (PP2C) gene relation to stress tolerance in Arabidopsis thaliana.

Protein phosphatases type 2C (PP2Cs) from group A, which includes the ABI1/HAB1 and PP2CA branches, are key negative regulators of ABA signaling. HAI-1 gene had been shown to affect both seed and vegetative responses to ABA, which is one of PP2Cs clade A in Arabidopsis thaliana. Transgenic plants containing pHAI-1::GUS (ß-glucuronidase) displayed GUS activity existing in the vascular system of leave veins, stems and petioles. Green fluorescent protein fused HAI-1 (HAI-1-GFP) was found in the nucleus through transient transformation assays with onion epidermal cells. The water-loss assays indicated the loss-of-function mutants did not show symptoms of wilting and they had still turgid green rosette leaves. The assays of seed germination by exogenous ABA and NaCl manifested that the loss-of-function mutants displayed higher insensitivity than wild-type plants. Taken together, the final results suggest that the HAI-1 (AT5G59220) encoded a nuclear protein and it can be highly induced by ABA and wound in Arabidposis, the stress-tolerance phenotype showed a slightly improvement when HAI-1 gene was disrupted.

Characterization of the complete mitochondrial genome of the longhorn beetle, Batocerahorsfieldi (Coleoptera, Cerambycidae) and its phylogenetic analysis with suitable longhorn beetles.

Mitochondrial genome analysis is an important tool for studying insect phylogenetics. The longhorn beetle, Batocerahorsfieldi, is a significant pest in timber, economic and protection forests. This study determined the mitochondrial genome of B.horsfieldi and compared it with the mitochondrial genomes of other Cerambycidae with the aim of exploring the phylogenetic status of the pest and the evolutionary relationships among some Cerambycidae subgroups. The complete mitochondrial genome of B.horsfieldi was sequenced by the Illumina HiSeq platform. The mitochondrial genome was aligned and compared with the existing mitochondrial genomes of Batoceralineolata and B.rubus in GenBank (MF521888, MW629558, OM161963, respectively). The secondary structure of transfer RNA (tRNA) was predicted using tRNAScan-SE server v.1.21 and MITOS WebSever. Thirteen protein-coding genes (PCGs) and two ribosomal RNA gene sequences of 21 longhorn beetles, including B.horsfieldi, plus two outgroups, Dryopsernesti (Dryopidae) and Heterocerusparallelus (Heteroceridae), were analyzed. The phylogenetic tree was constructed using maximum likelihood and Bayesian inference methods. In this study, we successfully obtained the complete mitochondrial genome of B.horsfieldi for the first time, which is 15 425 bp in length. It contains 37 genes and an A + T-rich region, arranged in the same order as the recognized ancestor of longhorn beetles. The genome of B.horsfieldi is composed of 33.12% A bases, 41.64% T bases, 12.08% C bases, and 13.16% G bases. The structure, nucleotide composition, and codon usage of the new mitochondrial genome are not significantly different from other longhorn mitochondrial genomes. Phylogenetic analyses revealed that Cerambycidae formed a highly supported single clade, and Vesperidae was either clustered with Cerambycidae or formed a separate clade. Interestingly, B.horsfieldi, B.rubus and B.lineolata were clustered with Monochamus and Anoplophora species in both analyses, with high node support. Additionally, the VesperidaeSpiniphilusspinicornis and Vesperussanzi and the 19 Cerambycidae species formed a sister clade in the Bayesian analysis. Our results have produced new complete mitogenomic data, which will provide information for future phylogenetic and taxonomic research, and provide a foundation for future relevant research.

The genetic and physiological analysis of late-flowering phenotype of T-DNA insertion mutants of AtCAL1 and AtCAL2 in Arabidopsis.

The homozygous T-DNA mutants of AtCAL1 (Rat1) and AtCAL2 (Rat2) were obtained. The double mutant of Rat2/Rat1RNAi was constructed which showed obvious late-flowering phenotype from others. The expression of various flowering-related genes was studied among mutants and wild-type plants by quantitative RT-PCR. The double mutant plants showed the shortest root length compared with T-DNA insertion mutants and wild type plants under red light, blue light, and white light. The double mutants showed hypersensitivity to NaCl and ABA. However, these mutants had no effect on stomatal closure by ABA.

Edaravone Improves the Post-traumatic Brain Injury Dysfunction in Learning and Memory by Modulating Nrf2/ARE Signal Pathway.

OBJECTIVES: To investigate the molecular mechanism of edaravone (EDA) in improving the post-traumatic brain injury (TBI) dysfunction in learning and memory. METHODS: In vitro and in vivo TBI models were established using hydrogen peroxide (H2O2) treatment for hippocampal nerve stem cells (NSCs) and surgery for rats, followed by EDA treatment. WST 1 measurement, methylthiazol tetrazolium assay, and flow cytometry were performed to determine the activity, proliferation, and apoptosis of NSCs, and malondialdehyde (MDA), lactic dehydrogenase (LDH), and reactive oxygen species (ROS) detection kits were used to analyze the oxides in NSCs. RESULTS: Following EDA pretreatment, NSCs presented with promising resistance to H2O2-induced oxidative stress, whereas NSCs manifested significant increases in activity and proliferation and a decrease in apoptosis. Meanwhile, for NSCs, EDA pretreatment reduced the levels of MDA, LDH, and ROS, with a significant upregulation of Nrf2/antioxidant response element (ARE) signaling pathway, whereas for EDA-treated TBI rats, a significant reduction was observed in the trauma area and injury to the hippocampus, with improvement in memory and learning performance and upregulation of Nrf2/ARE signaling pathway. CONCLUSIONS: EDA, by regulating the activity of Nrf2/ARE signal pathway, can improve the TBI-induced injury to NSCs and learning and memory dysfunction in rats.

Opportunities to improve China's biodiversity protection laws.

Since 1989, China has established a system of powerful laws and regulations aimed to preserve its rich natural flora and fauna. However, this legislative framework still has shortcomings, in terms of sentencing standards across related crimes and the extent of scientific basis for sentences. Here, we review Chinese biodiversity protection laws and some example cases with the goal of suggesting ways to increase law compliance and thus better protect biodiversity. In particular, our suggestions involve regular updates of threat assessments based on scientific evidence including herbaceous plants, fungi and algae; considering ecological differences among the species groups and ensuing ecological damage and financial profit gained; and a differentiation of punishment between organized and individual crimes, with a preference for custodial sentences for the former and monetary fines for the latter, to comply better with international standards and to minimize the incentive to engage in such conduct.

The Potential Role of CERS1 in Autophagy Through PI3K/AKT Signaling Pathway in Hypophysoma.

To explore the role and mechanism of CERS1 in hypophysoma and investigate whether CERS1 overexpression can change the autophagy process of hypophysoma, and then to explore whether CERS1's effect was regulated by the PI3K/AKT signaling pathway. Western blot and RT-PCR were used to analyze the expression or mRNA level of CERS1 at different tissues or cell lines. Afterwards, the occurrence and development of hypophysoma in vivo and in vitro, respectively, was observed by using CERS1 overexpression by lentivirus. Finally, MK-2206 and LY294002 were applied to discuss whether the role of CERS1 was regulated by the PI3K/AKT signaling pathway. Results show that the CERS1 expression and mRNA level in tumor or AtT-20 cells were decreased. CERS1 over-expressed by lentivirus could inhibit hypophysoma development in vivo and in vitro by reducing tumor volume and weight, weakening tumor proliferation and invasion, and enhancing apoptosis. In addition, shCERS1 could reverse the process. The above results indicate that CERS1 is possibly able to enhance autophagy in hypophysoma through the PI3K/AKT signaling pathway.

Crystal structure of the extracellular domain of the receptor-like kinase TMK3 from Arabidopsis thaliana.

Transmembrane kinases (TMKs) are members of the plant receptor-like kinase (RLK) family. TMKs are characterized by an extracellular leucine-rich-repeat (LRR) domain, a single transmembrane region and a cytoplasmic kinase domain. TMKs have been shown to act as critical modulators of cell expansion and cell proliferation. Here, the crystal structure of the extracellular domain of TMK3 (TMK3-ECD) was determined to a resolution of 2.06 Å, with an Rwork of 17.69% and an Rfree of 20.58%. Similar to the extracellular domain of TMK1, the TMK3-ECD structure contains two solenoids with 13 LRRs and a non-LRR region (316-364) between the tenth and 11th LRRs. A comparison of TMK3-ECD with other LRR-RLKs that contain a non-LRR region indicates that the non-LRR region plays a critical role in structural integrity and may contribute to ligand interactions. The non-LRR region of TMK3-ECD is characterized by two disulfide bonds that may have critical biological implications.

RALF1-FERONIA complex affects splicing dynamics to modulate stress responses and growth in plants.

The environmentally responsive signaling pathways that link global transcriptomic changes through alternative splicing (AS) to plant fitness remain unclear. Here, we found that the interaction of the extracellular rapid alkalinization FACTOR 1 (RALF1) peptide with its receptor FERONIA (FER) triggered a rapid and massive RNA AS response by interacting with and phosphorylating glycine-rich RNA binding protein7 (GRP7) to elevate GRP7 nuclear accumulation in Arabidopsis thaliana. FER-dependent GRP7 phosphorylation enhanced its mRNA binding ability and its association with the spliceosome component U1-70K to enable splice site selection, modulating dynamic AS. Genetic reversal of a RALF1-FER-dependent splicing target partly rescued mutants deficient in GRP7. AS of GRP7 itself induced nonsense-mediated decay feedback to the RALF1-FER-GRP7 module, fine-tuning stress responses, and cell growth. The RALF1-FER-GRP7 module provides a paradigm for regulatory mechanisms of RNA splicing in response to external stimuli.

Long non-coding RNA BLACAT1 promotes the proliferation and invasion of glioma cells via Wnt/ß-catenin signaling.

Long non-coding RNAs (lncRNAs) are hypothesized to regulate numerous biological behaviors in human cancers. The present study aimed to explore the roles of lncRNA bladder cancer associated transcript 1 (BLACAT1) in glioma. The expression of BLACAT1 in glioma tissues and cell lines was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). CCK-8 assay, colony formation assay, wound healing assay and Transwell invasion assay were used to explore the roles of BLACAT1 in glioma cells. RT-qPCR and western blot analysis were used to determine the BLACAT1 molecular mechanism. The findings demonstrated that lncRNA BLACAT1 was overexpressed in glioma tissues and cell lines. High BLACAT1 expression was correlated with high tumor grade in glioma patients. Functional assays determined that BLACAT1 promoted glioma cell proliferation, migration, invasion and epithelial-mesenchymal transition in vitro. In addition, it was demonstrated that BLACAT1 activated the Wnt/ß-catenin signaling pathway. In conclusion, BLACAT1 may serve as an oncogenic lncRNA in glioma progression via activation of the Wnt/ß-catenin signaling pathway. Therefore, BLACAT1 may be a novel therapeutic target for glioma treatment.

Species richness of Eurasian Zephyrus hairstreaks (Lepidoptera: Lycaenidae: Theclini) with implications on historical biogeography: An NDM/VNDM approach.

AIM: A database based on distributional records of Eurasian Zephyrus hairstreaks (Lepidoptera: Lycaenidae: Theclini) was compiled to analyse their areas of endemism (AoEs), species richness and distribution patterns, to explore their locations of past glacial refugia and dispersal routes. METHODS: Over 2000 Zephyrus hairstreaks occurrences are analysed using the NDM/VNDM algorithm, for the recognition of AoEs. Species richness was calculated by using the option 'Number of different classes' to count the different classes of a variable presented in each 3.0°×3.0° grid cell, and GIS software was used to visualize distribution patterns of endemic species. RESULTS: Centres of species richness of Zephyrus hairstreaks are situated in the eastern Qinghai-Tibet Plateau (EQTP), Hengduan Mountain Region (HDMR) and the Qinling Mountain Region (QLMR). Latitudinal gradients in species richness show normal distribution with the peak between 25° N and 35° N in the temperate zone, gradually decreasing towards the poles. Moreover, most parts of central and southern China, especially the area of QLMR-EQTP-HDMR, were identified as AoEs that may have played a significant role as refugia during Quaternary global cooling. There are four major distributional patterns of Zephyrus hairstreaks in Eurasia: Sino-Japanese, Sino-Himalayan, high-mountain and a combined distribution covering all three patterns. CONCLUSIONS: Zephyrus hairstreaks probably originated at least 23-24 Myr ago in E. Asia between 25° N to 35° N in the temperate zone. Cenozoic orogenies caused rapid speciation of this tribe and extrusion of the Indochina block resulted in vicariance between the Sino-Japanese and the Sino-Himalayan patterns. The four distribution patterns provided two possible dispersal directions: Sino-Japanese dispersal and Sino-Himalayan dispersal.

MicroRNA-143 shows tumor suppressive effects through inhibition of oncogenic K-Ras in pituitary tumor.

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, about 21-25 nucleotides in length. Accumulating evidence demonstrated that dysregulation or dysfunction of miRNAs are involved in various diseases, including cancer. MiR-143, recently has been reported to function as an important tumor suppressor in prostate cancer, pancreatic ductal adenocarcinoma and other kinds of cancers, but rarely systematically studied in pituitary tumor. In the present study, we firstly found that miR-143 was significantly down-regulated in pituitary tumor tissues and cell lines (GH3 and MMQ). Then, subsequent studies revealed that miR-143 inhibits cell proliferation and promotes apoptosis in both GH3 and MMQ cells. In addition, K-Ras, one of the most important oncogenes involved in many kinds of cancers, was found to be suppressed by miR-143 in pituitary tumor. Furthermore, overexpression of K-Ras greatly reversed the suppressive effect of miR-143 on pituitary tumor cells. In summary, our study demonstrated that miR-143 functions as a tumor suppressor and directly targets K-Ras in human pituitary tumor.