Anti-Corruption Campaign and Firm Financial Performance: Evidence From Vietnam Firms.

BACKGROUND: Corruption affects businesses in various ways. Anti-corruption, on the other hand, can improve the institutions of the country as well as business operations. Vietnam, as a socialist-oriented country with an ongoing high-profile anti-corruption campaign, provides us a unique setting to evaluate the impacts of anti-corruption on corporate performance. OBJECTIVES: We address two questions: (1) what is the effect of anti-corruption on the performance of private-owned firms in Vietnam? and (2) how does anti-corruption influence the performance of firms with state ownership (FSOs) in Vietnam? RESEARCH DESIGN: To investigate the impact of anti-corruption on performance of firms with different ownership settings, we use the establishment of the Central Anti-Corruption Steering Committee of Vietnam as a quasi-natural experiment for difference-in-differences analysis. We generate treatment effects of private holding and the state block ownership. To validate the findings, we construct a novel news-based anti-corruption index from Vietnamese online newspapers and use it in a robustness test to evaluate anti-corruption's impacts on firm performance. RESULTS AND CONCLUSIONS: We find a positive impact of the anti-corruption campaign on private firms' performance, supporting the social norm perspective of how corruption affects businesses. The empirical results indicate a negative impact of the campaign on FSOs' performance. The findings suggest that anti-corruption benefits private firms via improving the institutional quality of the country while improving the financial transparency of FSOs. Our study provides a method for measuring anti-corruption which is virtually unobservable and absent in the literature. The findings have implications for policymaking in contemporary Vietnam.

Mechanism of an ATP-independent protein disaggregase: I. structure of a membrane protein aggregate reveals a mechanism of recognition by its chaperone.

BACKGROUND: A novel chaperone, cpSRP43, recognizes and disassembles the aggregates formed by its client proteins. RESULTS: The client proteins of cpSRP43 form stable disc-shaped aggregates with the chaperone recognition motif displayed onthe surface. CONCLUSION: The surface-exposed motif on the aggregate allows it to be recognized by its chaperone. SIGNIFICANCE: Understanding the structure and energetics of protein aggregates provides insights into the mechanism of theirDISASSEMBLY.Protein aggregation is detrimental to the maintenance of proper protein homeostasis in all cells. To overcome this problem, cells have evolved a network of molecular chaperones to prevent protein aggregation and even reverse existing protein aggregates. The most extensively studied disaggregase systems are ATP-driven macromolecular machines. Recently, we reported an alternative disaggregase system in which the 38-kDa subunit of chloroplast signal recognition particle (cpSRP43) efficiently reverses the aggregation of its substrates, the light-harvesting chlorophyll a/b-binding (LHC) proteins, in the absence of external energy input. To understand the molecular mechanism of this novel activity, here we used biophysical and biochemical methods to characterize the structure and nature of LHC protein aggregates. We show that LHC proteins form micellar, disc-shaped aggregates that are kinetically stable and detergent-resistant. Despite the nonamyloidal nature, the LHC aggregates have a defined global organization, displaying the chaperone recognition motif on its solvent-accessible surface. These findings suggest an attractive mechanism for recognition of the LHC aggregate by cpSRP43 and provide important constraints to define the capability of this chaperone.

Mechanism of an ATP-independent protein disaggregase: II. distinct molecular interactions drive multiple steps during aggregate disassembly.

The ability of molecular chaperones to overcome the misfolding and aggregation of proteins is essential for the maintenance of proper protein homeostasis in all cells. Thus far, the best studied disaggregase systems are the Clp/Hsp100 family of "ATPases associated with various cellular activities" (AAA(+)) ATPases, which use mechanical forces powered by ATP hydrolysis to remodel protein aggregates. An alternative system to disassemble large protein aggregates is provided by the 38-kDa subunit of the chloroplast signal recognition particle (cpSRP43), which uses binding energy with its substrate proteins to drive disaggregation. The mechanism of this novel chaperone remains unclear. Here, molecular genetics and structure-activity analyses show that the action of cpSRP43 can be dissected into two steps with distinct molecular requirements: (i) initial recognition, during which cpSRP43 binds specifically to a recognition motif displayed on the surface of the aggregate; and (ii) aggregate remodeling, during which highly adaptable binding interactions of cpSRP43 with hydrophobic transmembrane domains of the substrate protein compete with the packing interactions within the aggregate. This establishes a useful framework to understand the molecular mechanism by which binding interactions from a molecular chaperone can be used to overcome protein aggregates in the absence of external energy input from ATP.

Concerted complex assembly and GTPase activation in the chloroplast signal recognition particle.

The universally conserved signal recognition particle (SRP) and SRP receptor (SR) mediate the cotranslational targeting of proteins to cellular membranes. In contrast, a unique chloroplast SRP in green plants is primarily dedicated to the post-translational targeting of light harvesting chlorophyll a/b binding (LHC) proteins. In both pathways, dimerization and activation between the SRP and SR GTPases mediate the delivery of cargo; whether and how the GTPase cycle in each system adapts to its distinct substrate proteins were unclear. Here, we show that interactions at the active site essential for GTPase activation in the chloroplast SRP and SR play key roles in the assembly of the GTPase complex. In contrast to their cytosolic homologues, GTPase activation in the chloroplast SRP-SR complex contributes marginally to the targeting of LHC proteins. These results demonstrate that complex assembly and GTPase activation are highly coupled in the chloroplast SRP and SR and suggest that the chloroplast GTPases may forego the GTPase activation step as a key regulatory point. These features may reflect adaptations of the chloroplast SRP to the delivery of their unique substrate protein.

A distinct mechanism to achieve efficient signal recognition particle (SRP)-SRP receptor interaction by the chloroplast srp pathway.

Cotranslational protein targeting by the signal recognition particle (SRP) requires the SRP RNA, which accelerates the interaction between the SRP and SRP receptor 200-fold. This otherwise universally conserved SRP RNA is missing in the chloroplast SRP (cpSRP) pathway. Instead, the cpSRP and cpSRP receptor (cpFtsY) by themselves can interact 200-fold faster than their bacterial homologues. Here, cross-complementation analyses revealed the molecular origin underlying their efficient interaction. We found that cpFtsY is 5- to 10-fold more efficient than Escherichia coli FtsY at interacting with the GTPase domain of SRP from both chloroplast and bacteria, suggesting that cpFtsY is preorganized into a conformation more conducive to complex formation. Furthermore, the cargo-binding M-domain of cpSRP provides an additional 100-fold acceleration for the interaction between the chloroplast GTPases, functionally mimicking the effect of the SRP RNA in the cotranslational targeting pathway. The stimulatory effect of the SRP RNA or the M-domain of cpSRP is specific to the homologous SRP receptor in each pathway. These results strongly suggest that the M-domain of SRP actively communicates with the SRP and SR GTPases and that the cytosolic and chloroplast SRP pathways have evolved distinct molecular mechanisms (RNA vs. protein) to mediate this communication.