Deciphering Proteomic Signatures of Early Diapause in Nasonia

Insect diapause is an alternative life-history strategy used to increase longevity and survival in harsh environmental conditions. Even though some aspects of diapause are well investigated, broader scale studies that elucidate the global metabolic adjustments required for this remarkable trait, are rare. In order to better understand the metabolic changes during early insect diapause, we used a shotgun proteomics approach on early diapausing and non-diapausing larvae of the recently sequenced hymenopteran model organism Nasonia vitripennis. Our results deliver insights into the molecular underpinnings of diapause in Nasonia and corroborate previously reported diapause-associated features for invertebrates, such as a diapause-dependent abundance change for heat shock and storage proteins. Furthermore, we observed a diapause-dependent switch in enzymes involved in glycerol synthesis and a vastly changed capacity for protein synthesis and degradation. The abundance of structural proteins and proteins involved in protein synthesis decreased with increasing diapause duration, while the abundance of proteins likely involved in diapause maintenance (e.g. ferritins) increased. Only few potentially diapause-specific proteins were identified suggesting that diapause in Nasonia relies to a large extent on a modulation of pre-existing pathways. Studying a diapause syndrome on a proteomic level rather than isolated pathways or physiological networks, has proven to be an efficient and successful avenue to understand molecular mechanisms involved in diapause

Relocation to get venture capital : a resource dependence perspective

This is the author accepted manuscript. The final version is available from SAGE via the DOI in this record.Using a resource dependence perspective, we theorize and show that non-venture-capital-backed ventures founded in U.S. states with a lower availability of venture capital (VC) are more likely to relocate to California (CA) or Massachusetts (MA)—the two VC richest states—compared to ventures founded in states with a greater availability of VC. Moreover, controlling for self-selection, ventures that relocate to CA or MA subsequently have a greater probability of attracting initial VC compared to ventures that stay in their home state. We discuss the implications for theory, future research, and practice

The Debt-Maturity Structure of Small Firms in a Creditor-Oriented Environment

Once a firm decides to issue debt, the characteristics of this debt instrument should be considered. One of the critical decisions involves debt maturity. Using a sample of 1091 Belgian small firms from 1996 until 2000, this study analyses the determinants of the corporate debt-maturity structure of small firms in a creditor-oriented system. Consistent with previous empirical evidence on large firms, the present results strongly support the maturity-matching principle. The hypothesis that firms with many growth opportunities will borrow on the short term as a response to the under-investment problem, is not supported. There is a clear relation between the credit worthiness of a firm and the debt-maturity structure. Firms with a better credit score borrow on the long term, whereas firms with a poor credit quality are apparently forced to borrow on the short term. This evidence contradicts the expected U-shaped relationship between credit worthiness and debt maturity. Size negatively influences debt maturity.debt maturity, capital structure, small firms