Herein, we describe simple, fast and reproducible halide ion exchange reactions in CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) at room temperature. Through the simple adjustment of the halide ion concentration, the photoluminescence of these NCs can be tuned over the entire visible region (425-655 nm). Photodetector devices based on entirely inorganic CsPbI3 NCs are demonstrated for the first time. The photodetectors exhibited a good on/off photocurrent ratio of 10(5).

Mutations in the BRCA1 (ref. 1) tumour suppressor gene are found in almost all of the families with inherited breast and ovarian cancers and about half of the families with only breast cancer. Although the biochemical function of BRCA1 is not well understood, it is important for DNA damage repair and cell-cycle checkpoint. BRCA1 exists in nuclear foci but is hyperphosphorylated and disperses after DNA damage. It is not known whether BRCA1 phosphorylation and dispersion and its function in DNA damage response are related. In yeast the DNA damage response and the replication-block checkpoint are mediated partly through the Cds1 kinase family. Here we report that the human Cds1 kinase (hCds1/Chk2) regulates BRCA1 function after DNA damage by phosphorylating serine 988 of BRCA1. We show that hCds1 and BRCA1 interact and co-localize within discrete nuclear foci but separate after gamma irradiation. Phosphorylation of BRCA1 at serine 988 is required for the release of BRCA1 from hCds1. This phosphorylation is also important for the ability of BRCA1 to restore survival after DNA damage in the BRCA1-mutated cell line HCC1937.

Autophagy is an active homeostatic degradation process for the removal or turnover of cytoplasmic components wherein the LC3 ubiquitin-like protein undergoes an Atg7 E1-like enzyme/Atg3 E2-like enzyme-mediated conjugation process to induce autophagosome biogenesis1–4. Besides its cytoprotecive role, autophagy acts on cell death when it is abnormally upregulated. Thus, the autophagy pathway requires tight regulation to ensure that this degradative process is well balanced. Two death effector domains (DED1/2) containing cellular FLICE-like inhibitor protein (cFLIP) and viral FLIP (vFLIP) of Kaposi’s sarcoma-associated herpesvirus (KSHV), Herpesvirus saimiri (HVS), and Molluscum contagiosum virus (MCV) protect cells from apoptosis mediated by death receptors5,6. Here, we report that cellular and viral FLIPs suppress autophagy by preventing Atg3 from binding and processing LC3. Consequently, FLIP expression effectively represses cell death with autophagy, as induced by rapamycin, an mTor inhibitor and an effective anti-tumour drug against KSHV-induced Kaposi’s sarcoma (KS) and primary effusion lymphoma (PEL)7,8. Remarkably, either a DED1 α2-helix ten amino-acid (α2) peptide or a DED2 α4-helix twelve amino-acid (α4) peptide of FLIP is individually sufficient for binding FLIP itself and Atg3, with the peptide interactions effectively suppressing Atg3–FLIP interaction without affecting Atg3-LC3 interaction, resulting in robust cell death with autophagy. Our study thus identifies a checkpoint of the autophagy pathway where cellular and viral FLIPs limit the Atg3-mediated step of LC3 conjugation to regulate autophagosome biogenesis. Furthermore, the FLIP-derived short peptides induce growth suppression and cell death with autophagy, representing biologically active molecules for potential anti-cancer therapies.