Question: Which enzyme does MLN4924 inhibit?

Context:
Finally, MLN4924, an investigational small molecule inhibitor of NEDD8-activating enzyme (NAE) that inhibits CRL, suppresses in vitro migration, proliferation and tube formation, as well as in vivo angiogenesis and tumorigenesis. 
MLN4924, a small molecule inhibitor of NEDD8 activating enzyme (NAE), has been reported to elicit an anti-tumor effect on various malignancies. 
The more targeted impact of NEDD8-activating enzyme on protein degradation prompted us to study MLN4924, an investigational NEDD8-activating enzyme inhibitor, in preclinical multiple myeloma models.
A gatekeeper residue for NEDD8-activating enzyme inhibition by MLN4924.
Treatment-emergent mutations in NAEβ confer resistance to the NEDD8-activating enzyme inhibitor MLN4924.
Quantifiable analysis of cellular pathway inhibition of a Nedd8-activating enzyme inhibitor, MLN4924, using AlphaScreen.
Cellular effects of a Nedd8-activating enzyme (NAE) inhibitor, MLN4924, using the AlphaScreen format were explored.
Quantitative proteomic analysis of cellular protein modulation upon inhibition of the NEDD8-activating enzyme by MLN4924.
Inactivation of the Cullin (CUL)-RING E3 ligase by the NEDD8-activating enzyme inhibitor MLN4924 triggers protective autophagy in cancer cells.
The Nedd8-activating enzyme inhibitor MLN4924 thwarts microenvironment-driven NF-κB activation and induces apoptosis in chronic lymphocytic leukemia B cells.
Inhibition of Nedd8-activating enzyme by MLN4924 prevents the conjugation of cullin proteins with NEDD8, resulting in inactivation of the entire family of CRLs.
Substrate-assisted inhibition of ubiquitin-like protein-activating enzymes: the NEDD8 E1 inhibitor MLN4924 forms a NEDD8-AMP mimetic in situ.
To inhibit cellular neddylation, we used a cell line with tetracycline-inducible expression of a dominant-negative form of the Nedd8 E2 enzyme or treatment of cells with the Nedd8 E1 inhibitor MLN4924
MLN4924 is a first-in-class experimental cancer drug that inhibits the NEDD8-activating enzyme, thereby inhibiting cullin-RING E3 ubiquitin ligases and stabilizing many cullin substrates
MLN4924 is a first-in-class cancer drug that inhibits the Nedd8-activating enzyme (NAE)
MLN4924 is an investigational agent that inhibits the Nedd8-activating enzyme, thereby neutralizing Cullin-RING ubiquitin ligases and preventing degradation of their substrates
We used MLN4924, a phase 2 oncology therapeutic, which targets and inhibits the NEDD8-activating enzyme pathway involved in the ubiquitin-proteasome system
Neddylation occurs through a multistep enzymatic process involving Nedd8 activating enzymes, and recent studies have shown that the pharmacological agent, MLN4924, can potently inhibit Nedd8 activating enzymes, thereby preventing neddylation of Cullin proteins and preventing the degradation of CRL target proteins
The stability of the NEDD8-MLN4924 adduct within the NAE active site blocks enzyme activity, thereby accounting for the potent inhibition of the NEDD8 pathway by MLN4924. 
MLN4924 is a first-in-class experimental cancer drug that inhibits the NEDD8-activating enzyme, thereby inhibiting cullin-RING E3 ubiquitin ligases and stabilizing many cullin substrates. 
The NEDD8-activating enzyme inhibitor, MLN4924, cooperates with TRAIL to augment apoptosis through facilitating c-FLIP degradation in head and neck cancer cells.
Initial testing of the investigational NEDD8-activating enzyme inhibitor MLN4924 by the pediatric preclinical testing program.
MLN4924, a NEDD8-activating enzyme inhibitor, is active in diffuse large B-cell lymphoma models: rationale for treatment of NF-{kappa}B-dependent lymphoma.
 MLN4924 is a first-in-class cancer drug that inhibits the Nedd8-activating enzyme (NAE). Herein, we report that MLN4924 inhibits Vpx/Vpr-induced SAMHD1 degradation by inhibiting the neddylation of E3 ubiquitin ligase and blocks macaque simian immunodeficiency virus (SIVmac) replication in myeloid cells.
Neddylation can be prevented by MLN4924, a drug that inhibits the nedd8-activating enzyme. We report that MLN4924 inhibits the neddylation of CRL4, blocking Vpx-induced degradation of SAMHD1 and maintaining the restriction.
 MLN4924 is a first-in-class experimental cancer drug that inhibits the NEDD8-activating enzyme, thereby inhibiting cullin-RING E3 ubiquitin ligases and stabilizing many cullin substrates. The mechanism by which MLN4924 inhibits cancer cell proliferation has not been defined, although it is accompanied by DNA rereplication and attendant DNA damage.
MLN4924 inhibits NAE (NEDD8 Activating Enzyme),
 MLN4924 is an investigational small-molecule inhibitor of NEDD8-activating enzyme (NAE) in clinical trials for the treatment of cancer. MLN4924 is a mechanism-based inhibitor, with enzyme inhibition occurring through the formation of a tight-binding NEDD8-MLN4924 adduct.
Ubiquitin-activating enzyme (UAE or E1) activates ubiquitin via an adenylate intermediate and catalyzes its transfer to a ubiquitin-conjugating enzyme (E2). MLN4924 is an adenosine sulfamate analogue that was identified as a selective, mechanism-based inhibitor of NEDD8-activating enzyme (NAE), another E1 enzyme, by forming a NEDD8-MLN4924 adduct that tightly binds at the active site of NAE, a novel mechanism termed substrate-assisted inhibition (Brownell, J.
(2010) elucidate the mechanism of action of MLN4924, a NEDD8-activating enzyme inhibitor. MLN4924 requires the activity of the enzyme to generate a NEDD8-adenylate analog that potently and selectively shuts down this posttranslational modification system.
 Cellular effects of a Nedd8-activating enzyme (NAE) inhibitor, MLN4924, using the AlphaScreen format were explored. MLN4924 acts as a substrate-assisted inhibitor of NAE by forming a tight binding Nedd8-MLN4924 adduct.
MLN4924 is a first-in-class cancer drug that inhibits the Nedd8-activating enzyme (NAE). Herein, we report that MLN4924 inhibits Vpx/Vpr-induced SAMHD1 degradation by inhibiting the neddylation of E3 ubiquitin ligase and blocks macaque simian immunodeficiency virus (SIVmac) replication in myeloid cells.
MLN4924 is a first-in-class experimental cancer drug that inhibits the NEDD8-activating enzyme, thereby inhibiting cullin-RING E3 ubiquitin ligases and stabilizing many cullin substrates. The mechanism by which MLN4924 inhibits cancer cell proliferation has not been defined, although it is accompanied by DNA rereplication and attendant DNA damage.
MLN4924 is an investigational small-molecule inhibitor of NEDD8-activating enzyme (NAE) in clinical trials for the treatment of cancer. MLN4924 is a mechanism-based inhibitor, with enzyme inhibition occurring through the formation of a tight-binding NEDD8-MLN4924 adduct.
Cellular effects of a Nedd8-activating enzyme (NAE) inhibitor, MLN4924, using the AlphaScreen format were explored. MLN4924 acts as a substrate-assisted inhibitor of NAE by forming a tight binding Nedd8-MLN4924 adduct.

Answer: MLN4924 is  an investigational small molecule inhibitor of NEDD8-activating enzyme (NAE).
Exact answer: NEDD8-activating enzyme