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Background: Haemoglobin H (HbH) disease is caused by a disorder of α-globin synthesis, and it results in a wide range of clinical symptoms. M6A methylation modification may be one of the mechanisms of heterogeneity. Therefore, this article explored the role of methyltransferase like 16 (METTL16) in HbH disease. Method: The results of epigenetic transcriptome microarray were analysed and verified through bioinformatic methods and qRT-PCR, respectively. The overexpression or knock down of METTL16 in K562 cells was examined to determine its role in reactive oxygen species (ROS), cell cycle processes or iron overload. YTH domain family protein 3 (YTHDF3) was knocked down in K562 cells and K562 cells overexpressing METTL16 via siRNA to investigate its function. In addition, haemoglobin expression was detected through benzidine staining. qRT-PCR, WB, methylated RNA Immunoprecipitation (MeRIP) and (RNA Immunoprecipitation) RIP experiments were conducted to explore the mechanism of intermolecular interaction. Results: METTL16, YTHDF3 and solute carrier family 5 member 3 (SLC5A3) mRNA and the methylation level of SLC5A3 mRNA were downregulated in HbH patients. Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) mRNA expression was negatively correlated with HGB content among patients with HbH-CS disease. Overexpression of METTL16 increased ROS and intracellular iron contents in K562 cells, changed the K562 cell cycle, reduced hemin-induced haemoglobin synthesis, increased the expressions of SLC5A3 and HBG and increased SLC5A3 mRNA methylation levels. Knockdown of METTL16 reduced ROS and intracellular iron contents in K562 cells. Hemin treatment of K562 cells for more than 14 days reduced the protein expressions of METTL16 and SLC5A3 and SLC5A3 mRNA methylation levels. Knockdown of YTHDF3 rescued the intracellular iron content changes induced by the overexpression of METTL16. The RIP experiment revealed that SLC5A3 mRNA can be enriched by METTL16 antibody. Conclusion: METTL16 may affect the expression of SLC5A3 by changing its m6A modification level and regulating ROS synthesis, intracellular iron and cycle of red blood cells. Moreover, METTL16 possibly affects the expression of haemoglobin through IGF2BP3, which regulates the clinical phenotype of HbH disease. [ABSTRACT FROM AUTHOR]

Nitrate transporter AtNRT2.1 is the key component of the inducible high-affinity nitrate transport system in Arabidopsis thaliana. AtNRT2.1 is primarily expressed in roots and known to be mainly involved under fluctuating nitrogen supply conditions. It is still unknown whether AtNRT2.1 is involved in plant responses to other nutrient fluctuations. In this study, we found that the expression of AtNRT2.1 was also upregulated by phosphate and sulfate resupply, which may indicate a novel role in regulating phosphate and sulfate responses. Our study also demonstrated that expression of the major Pi transporter (Pht1) family member, AtPHT1;2, was suppressed by nitrate starvation and induced by nitrate resupply and sulfate starvation in comparison to the continuous nutrient treatment. Moreover, this study also showed that expression of sulfur transporter SULTR1;1 and AtNRT2.1 was suppressed by complete nutrient starvation and induced by complete nutrient resupply. These novel results provide strong evidence that there is crosstalk among the nitrate, sulfate, and phosphate transporters in regulating different nutrient fluctuations in Arabidopsis roots. Key words: Arabidopsis thaliana, AtNRT2.1, AtPHT1 2, SULTR1 1, nitrate, phosphate, sulfate, qPCR, Northern blot. Le transporteur des nitrates AtNRT2,1 constitue une composante cle du systeme inductible du transport de nitrates a haute affinite (STHA) chez l'Arabidopsis thaliana. Le AtNRT2,1 s'exprime surtout dans les racines et est connu surtout pour son implication sous des conditions variables d'apport en N. On ne sait toujours pas si le AtNRT2,1 est implique dans la reaction des plantes aux fluctuations d'autres elements. Dans cette etude, les auteurs ont constate que l'expression du AtNRT2,1 est egalement regulee a la hausse par un nouvel apport de P et de S, ce qui pourrait indiquer une nouvelle fonction dans la regulation des reactions aux P et S. Les resultats demontrent egalement que l'expression du principal membre de la famille des transporteurs du Pi (Pht 1), le AtPHT1 2, est supprime par une carence en nitrate et induit par un nouvel apport de nitrate en absence de sulfate, comparativement a un apport continu de nutriments. De plus, cette etude montre que l'expression du transporteur du soufre SULTR1 1 et AtNRT2,1 se voit supprimee par une privation complete de nutriments et induite par un nouvel apport complet de nutriments. Ces resultats inedits fournissent une preuve robuste de l'existence d'interventions croisees entre les transporteurs des nitrates, des sulfates et des phosphates dans la regulation des fluctuations des differents nutriments, chez les racines de l'Arabidopsis. Mots-cles : Arabidopsis thaliana, AtNRT2.1, AtPHT1;2, SULTR1;1, nitrate, phosphate, sulfate, qPCR, transfert de Northern. [Traduit par la Redaction], Introduction Nitrate, sulfate, and phosphate are all major macronutrients required for plant growth and development (Rouached et al. 2011b). In higher plants, they are available in the form of inorganic [...]

The short neuropeptide F (sNPF) and NPF receptor (NPFR) genes play important roles in many physiological processes. However, information on the survival‐related functions of sNPF and NPFR under different stress conditions is lacking in aphids. In this study, we cloned sNPF and NPFR, and investigated the expression levels of these genes in different developmental stages, wing morphs, and stress conditions of the bird cherry‐oat aphid (Rhopalosiphum padi L.), an important agricultural pest. The sNPF and NPFR transcript levels varied among developmental stages, and their expression levels in alate females were significantly higher than those in apterous females. In addition, starvation resulted in significantly increased sNPF expression, which then recovered after refeeding. Heat stress and insecticides significantly affected transcription of both genes. sNPF and NPFR knockdown in R. padi using RNA interference revealed optimal interference efficiency at 48 h post‐injection. sNPF knockdown significantly decreased adult longevity, 15‐d fecundity, and food intake. Additionally, mortality under starvation, insecticides, and heat stress conditions was significantly higher after injection with double‐stranded sNPF in R. padi. NPFR knockdown significantly affected food intake and starvation resistance in R. padi. These results strongly indicate that sNPF plays vital roles in food intake, longevity, and reproduction in R. padi, and it can significantly affect the pest's response to stress conditions. [ABSTRACT FROM AUTHOR]