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In comparison to mouse, the developmental process of human islets has not been properly elucidated. The advancement of single cell RNA-seq technology enables us to study the properties of alpha and beta cells at single cell resolution. By using mitochondrial genome variants as endogenous lineage-tracing markers, we found that human alpha and beta cells have different lineage features. This finding suggests specific endocrine progenitors for alpha and beta cells, which is different from mouse islet cells. This strategy was also applied to a study of chemically-induced islet cell reprogramming and was used to help identify artemether-induced alpha-to-beta trans-differentiation in human islets. The computational results of this study will inspire future studies to establish, maintain, and expand beta cell-specific progenitors in vitro and in vivo.

LncRNAs are emerging as integral functional and regulatory components of normal biological activities and are now considered as critically involved in the development of different diseases including cancer. In this review, we summarized recent findings on maternally expressed gene 3 (MEG3), a noncoding lncRNA, locates in the imprinted DLK1-MEG3 locus on human chromosome 14q32.3 region. MEG3 is expressed in normal tissues but is either lost or decreased in many human tumors and tumor derived cell lines. Studies have demonstrated that MEG3 is associated with cancer initiation, progression, metastasis and chemo-resistance. MEG3 may affect the activities of TP53, MDM2, GDF15, RB1 and some other key cell cycle regulators. In addition, the level of MEG3 showed good correlation with cancer clinicopathological grade. In summary, MEGs is an RNA-based tumor suppressor and is involved in the etiology, progression, and chemosensitivity of cancers. The alteration of MEG3 levels in various cancers suggested the possibility of using MEG3 level for cancer diagnosis and prognosis.

Activation of the innate immune system before the invasion of pathogens is a promising way to improve the resistance of plant against infection while reducing the use of agricultural chemicals. Although several elicitors were used to induce the resistance of potato plant to microbial pathogen infection, the role of curdlan oligosaccharide (CurdO) has not been established. In the current study, the defense responses were investigated at biochemical and proteomic levels to elucidate the elicitation effect of CurdOs in foliar tissues of potato (Solanum tuberosum L. cv. McCain G1). The results indicate that the CurdOs exhibit activation effect on the early- and late-defense responses in potato leaves. In addition, glucopentaose was proved to be the shortest active curdlan molecule based on the accumulation of H₂O₂ and salicylic acid and the activities of phenylalanine amino-lyase, β-1,3-glucanase and chitinase. The 2D-PAGE analysis reveals that CurdOs activate the integrated response reactions in potato cells, as a number of proteins with various functions are up-regulated including disease/defense, metabolism, transcription, and cell structure. The pathogenesis assay shows that the ratio of lesion area of potato leaf decreased from 15.82%±5.44% to 7.79%±3.03% when the plants were treated with CurdOs 1 day before the infection of Phytophthora infestans. Furthermore, the results on potato yield and induction reactions indicate that the defense responses induced by CurdOs lasted for short period of time but disappeared gradually.