Nqo1

Case study 1: Hong-Jun Kang, 2018

Previous studies have shown that SIRT2 plays a role in mitosis through deacetylating specific downstream targets. However, the upstream regulation of SIRT2 activity has been relatively unexplored. In this study, the researchers provide evidence that NAD(P)H:quinone oxidoreductase 1 (NQO1) interacts with and activates SIRT2 in an NAD-dependent manner. Strong protein-protein interaction and co-localization of the two proteins during mitosis is required to maintain an active NQO1-SIRT2 axis which is critical for successful completion of mitosis. In this regard, both pharmacologic and genetic NQO1 inhibition increases sensitivity to anti-mitotic drugs functioning as microtubule poisons by inducing mitotic arrest and allowing cells to accumulate cell death signals. Therefore, the significant prognostic value of NQO1 in predicting outcome of cancer patients might be explained in part due to the functional contribution of NQO1-SIRT2 axis to mitotic stress.

Fig1. MCF-7 cells were transiently transfected with Flag-NQO1 and HA-SIRT2.

Fig2. Reciprocal co-immunoprecipitation of endogenous SIRT2 and NQO1 in either unsynchronized or synchronized in mitosis Hela cells.

Case study 2: Duojun Qiu, 2023

Diabetic nephropathy (DN) is one of the main complications of diabetes, and inflammation and fibrosis play an important role in its progression. NAD(P)H: quinone oxidoreductase 1 (NQO1) protects cells from oxidative stress and damage caused by toxic quinones. In the present study, the researchers aimed to investigate the protective effects of NQO1 against diabetes-induced renal inflammation and fibrosis and the underlying mechanisms.

In vitro, human renal tubular epithelial (HK-2) cells transfected with NQO1 pcDNA3.1(+) were cultured under high-glucose (HG) conditions. Gene and protein expression was assessed by quantitative real-time PCR, Western blotting, immunofluorescence, and immunohistochemical staining. Overexpression of NQO1 suppressed proinflammatory cytokine (IL-6, TNF-α, MCP-1) secretion, extracellular matrix (ECM) (collagen IV, fibronectin) accumulation and epithelial-mesenchymal transition (EMT) (α-SMA, E-cadherin) in the db/db mouse kidneys and HG-cultured HK-2 cells. Furthermore, NQO1 overexpression ameliorated HG-induced TLR4/NF-κB and TGF-β/Smad pathways activation. This study suggest that NQO1 alleviates diabetes-induced renal inflammation and fibrosis by regulating the TLR4/NF-κB and TGF-β/Smad signaling pathways.

Fig3. NQO1 overexpression blocked HG-induced fibronectin and collagen IV expression in HK-2 cells.

Fig4. Effect of the antioxidants tempol and NAC on NQO1, TLR4, TGF-β1, Nox1 and Nox4 expression and ROS generation in HG-cultured HK-2 cells.

Fig1. Schematic representation of NQO1 regulation in ovarian cancer cells. (Giovanni Tossetta, 2023)

Fig2. Schematic model showing how NQO1 regulates cell cycle progression at the G2/M phase in cancer cells. (Eun-Taex Oh, 2023)

Nqo1 involved in several pathways and played different roles in them. We selected most pathways Nqo1 participated on our site, such as AhR pathway, Dopamine metabolism, Estrogen metabolism, which may be useful for your reference. Also, other proteins which involved in the same pathway with Nqo1 were listed below. Creative BioMart supplied nearly all the proteins listed, you can search them on our site.

Nqo1 has several biochemical functions, for example, NAD(P)H dehydrogenase (quinone) activity, cytochrome-b5 reductase activity, acting on NAD(P)H, identical protein binding. Some of the functions are cooperated with other proteins, some of the functions could acted by Nqo1 itself. We selected most functions Nqo1 had, and list some proteins which have the same functions with Nqo1. You can find most of the proteins on our site.

Nqo1 has direct interactions with proteins and molecules. Those interactions were detected by several methods such as yeast two hybrid, co-IP, pull-down and so on. We selected proteins and molecules interacted with Nqo1 here. Most of them are supplied by our site. Hope this information will be useful for your research of Nqo1.

ING1; Tp63; Tp63; NDUFS7; VCAM1