Chang-Wook Lee

autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.

Repression of E2F transcription activity by the retinoblastoma (Rb) tumor suppressor through its interaction with the transactivation domain of the E2F transcription factor is one of the central features of G1/S arrest in the mammalian cell cycle. Deregulation of the Rb-E2F interaction results in hyperproliferation, lack of differentiation, and apoptosis, and can lead to cancer. The 2.2-A crystal structure of the Rb pocket complexed with an 18-residue transactivation-domain peptide of E2F-2 reve

The mitochondrial pool of Hsp90 and its mitochondrial paralogue, TRAP1, suppresses cell death and reprograms energy metabolism in cancer cells; therefore, Hsp90 and TRAP1 have been suggested as target proteins for anticancer drug development. Here, we report that the actual target protein in cancer cell mitochondria is TRAP1, and current Hsp90 inhibitors cannot effectively inactivate TRAP1 because of their insufficient accumulation in the mitochondria. To develop mitochondrial TRAP1 inhibitors,

The endoplasmic reticulum (ER)-mitochondria encounter structure (ERMES) comprises mitochondrial distribution and morphology 12 (Mdm12), maintenance of mitochondrial morphology 1 (Mmm1), Mdm34, and Mdm10 and mediates physical membrane contact sites and nonvesicular lipid trafficking between the ER and mitochondria in yeast. Herein, we report two crystal structures of the synaptotagmin-like mitochondrial lipid-binding protein (SMP) domain of Mmm1 and the Mdm12-Mmm1 complex at 2.8 Å and 3.8 Å resol

The current follow-up 1H MR spectroscopy study shows a significant correlation between alterations of (GABA + Glu)/Cr ratio and BPRS, and supports a hypofrontality hypothesis in chronic schizophrenia. The reduction of (GABA + Glu)/Cr ratio after neuroleptic treatment may implicate the recovery of normal neuronal function in neurotransmitters. In vivo 1H MR spectroscopy may be a useful modality in follow-up evaluation of neuroleptic treatment in chronic schizophrenia.

ions between these organelles. Mitoguardin-2 (MIGA2), a mitochondrial outer membrane protein, forms the ERMCS in higher eukaryotic cells. Here, we report the crystal structures of the MIGA2 Lipid Droplet (LD) targeting domain and the ER membrane protein VAPB bound to the phosphorylated FFAT motif of MIGA2. These structures reveal that the MIGA2 LD targeting domain has a large internal hydrophobic pocket that accommodates phospholipids and that two phosphorylations of the FFAT motif are required

NFκB is a central mediator of inflammation. Present inhibitors of NFκB are mostly based on inhibition of essential machinery such as proteasome and protein kinases, or activation of nuclear receptors; as such, they are of limited therapeutic use due to severe toxicity. Here we report an LPS-induced NFκB enhanceosome in which TonEBP is required for the recruitment of p300. Increased expression of TonEBP enhances the NFκB activity and reduced TonEBP expression lowers it. Recombinant TonEBP molecul

In eukaryotes, misfolded proteins must be distinguished from correctly folded proteins during folding and transport processes by quality control systems. Yeast peptide:N-glycanase (yPNGase) specifically deglycosylates the denatured form of N-linked glycoproteins in the cytoplasm and assists proteasome-mediated glycoprotein degradation by forming a complex with 26S proteasome through DNA repair protein, yRad23. Here, we describe the crystal structures of a yPNGase and XPC-binding domain of yRad23

Mammalian target of rapamycin (mTOR) signaling is a core pathway in cellular metabolism, and control of the mTOR pathway by rapamycin shows potential for the treatment of metabolic diseases. In this study, we employed a new proximity biotin-labeling method using promiscuous biotin ligase (pBirA) to identify unknown elements in the rapamycin-induced interactome on the FK506-rapamycin binding (FRB) domain in living cells. FKBP25 showed the strongest biotin labeling by FRB-pBirA in the presence of

Although Hsp90 inhibitors can inhibit multiple tumorigenic pathways in cancer cells, their anticancer activity has been disappointingly modest. However, by forcing Hsp90 inhibitors into the mitochondria with mitochondrial delivery vehicles, they were converted into potent drugs targeting the mitochondrial Hsp90 paralog TRAP1. Here, to improve mitochondrial drug accumulation without using the mitochondrial delivery vehicle, we increased freely available drug concentrations in the cytoplasm by red

We introduce UnaG as a green-to-dark photoswitching fluorescent protein capable of high-quality super-resolution imaging with photon numbers equivalent to the brightest photoswitchable red protein. UnaG only fluoresces upon binding of a fluorogenic metabolite, bilirubin, enabling UV-free reversible photoswitching with easily controllable kinetics and low background under Epi illumination. The on- and off-switching rates are controlled by the concentration of the ligand and the excitation light i

Significance Organelle contact sites are specialized intracellular zones called membrane contact sites (MCS), in which two distinct suborganelles are closely apposed in eukaryotic cells. The nucleus–vacuole junction (NVJ) is the first identified interorganellar MCS in the budding yeast Saccharomyces cerevisiae , and its formation depends on the nuclear membrane protein Nvj1p and vacuolar membrane protein Vac8p. We present the crystal structure of Vac8p–Nvj1p complex at 2.4-Å resolution. Based on