Where are the returns to lifelong learning?

Participation in formal education during adulthood (ages 25 to 54) is a key part of lifelong learning. Employing unique longitudinal data for Australia, we highlight the prevalence of such study, the varied reasons for undertaking it (consumption, career development, job and home disruption), and investigate whether it is socially valuable. Our more detailed estimates of the labour market return to adult education (wage rates, employment, hours of work and occupational status) confirm previous studies that generally found such returns to be small and isolated. We contribute to this literature by also estimating the effect of adult education on job satisfaction and satisfaction with employment opportunities. Increases in satisfaction help rationalise the education enrolment decisions of these adults

The effects of over-education on earnings in the graduate labour market

This paper uses a new survey of graduates from one large civil university in the UK to examine the determinants of overeducation and its subsequent impact on labour market earnings. Multiple measurements of over-education were collected to assess the effect of measurement error on the estimated pay penalty associated with over-education. Panel estimates suggest that the upward bias in standard OLS estimates is offset by an equal downward bias resulting from measurement error

Targeting of aminopeptidase I to the yeast vacuole is mediated by Ssa1p, a cytosolic member of the 70-kDa stress protein family

The two cytosolic members of the highly conserved 70-kDa stress protein family, Ssa1p and Ssa2p, were specifically retained by the prepro-NH2 extension of the vacuolar aminopeptidase I precursor (pAPI) conjugated to agarose (Sulfolink). A temperature-sensitive mutant strain a1(ts)a234 (ssa1(ts) ssa2 ssa3 ssa4), when incubated at the restrictive temperature, was able to assemble the API precursor into dodecamers, but failed to pack pAPI into vesicles and to convert it into mature API (mAPI), a process that occurs in the vacuole. Altogether these results indicate that Ssa1p mediates the targeting of pAPI to the vacuole.This work was supported by a grant from the European Community (EC) (FMRX-CT96-0058) (to I. V. S. and M. J. M.) and by grants from the Comisión Interministerial de Ciencia y Tecnología (94-0035) (to I. V. S.) and the Fondo de Investigaciones Sanitarias (98/279) (to M. J. M.).Peer Reviewe

Synthesis of bisphosphonate derivatives of ATP by T4 RNA ligase

Open Access.T4 RNA ligase catalyzes the synthesis of ATP β,γ-bisphosphonate analogues, using the following substrates with the relative velocity rates indicated between brackets: methylenebisphosphonate (pCH2p) (100), clodronate (pCCl2p) (52), and etidronate (pC(OH)(CH3)p) (4). The presence of pyrophosphatase about doubled the rate of these syntheses. Pamidronate (pC(OH)(CH2-CH2-NH2)p), and alendronate (pC(OH)(CH2-CH2-CH2-NH2)p) were not substrates of the reaction. Clodronate displaced the AMP moiety of the complex E-AMP in a concentration dependent manner. The Km values and the rate of synthesis (kcat) determined for the bisphosphonates as substrates of the reaction were, respectively: methylenebisphosphonate, 0.26 ± 0.05 mM (0.28 ± 0.05 s-1); clodronate, 0.54 ± 0.14 mM (0.29 ± 0.05 s-1); and etidronate, 4.3 ± 0.5 mM (0.028 ± 0.013 s-1). In the presence of GTP, and ATP or AppCCl2p the relative rate of synthesis of adenosine 5′,5‴-P1,P4-tetraphosphoguanosine (Ap4G) was around 100% and 33%, respectively; the methylenebisphosphonate derivative of ATP (AppCH2p) was a very poor substrate for the synthesis of Ap4G. To our knowledge this report describes, for the first time, the synthesis of ATP β,γ-bisphosphonate analogues by an enzyme different to the classically considered aminoacyl-tRNA synthetases. © 2006 Federation of European Biochemical Societies.This investigation was supported by grants from Dirección General de Investigación Científica y Técnica (BFU2006-04307/BMC) and Instituto de Salud Carlos III (C03/08).Peer Reviewe

The effects of over-education on earnings in the graduate labour market

This paper uses a new survey of graduates from one large civil university in the UK to examine the determinants of over-education and its subsequent impact on labour market earnings. Multiple measurements of over-education were collected to assess the effect of measurement error on the estimated pay penalty associated with over-education. Panel estimates suggest that the upward bias in standard OLS estimates is offset by an equal downward bias resulting from measurement error.

Yo1082p, a novel CVT protein involved in the selective targeting of aminopeptidase I to the yeast vacuole

The yeast vacuolar enzyme aminopeptidase I (API) is synthesized in the cytoplasm as a precursor (pAPI). Upon its assembly into dodecamers, pAPI is wrapped by double-membrane saccular structures for its further transport within vesicles that fuse with the vacuolar membrane and release their content in the vacuolar lumen. Targeting of API to the vacuole occurs by two alternative transport routes, the cvt and the autophagy pathways, which although mechanistically similar specifically operate under vegetative growth or nitrogen starvation conditions, respectively. We have studied the role of Yo1082p, a protein identified by its ability to interact with API, in the transport of its precursor to the vacuole. We show that Yo1082p interacts with mature API, an interaction that is strengthened by the amino extension of the API protein. Yo1082p is required for targeting of pAPI to the vacuole, both under growing and short term nitrogen starvation conditions. Absence of Yo1082p does not impede the assembly of pAPI into dodecamers, but precludes the enclosure of pAPI within transport vesicles. Microscopy studies show that during vegetative growth Yo1082p is distributed between a cytoplasmic pool and a variable number of 0.13-0.27-μm round, mobile structures, which are no longer observed under conditions of nitrogen starvation, and become larger in cells expressing the inactive Yo1082AC32p, or lacking Apg12p. In contrast to the autophagy mutants involved in API transport, a Δyo1082 strain does not lose viability under nitrogen starvation conditions, indicating normal function of the autophagy pathway. The data are consistent with a role of Yo1082p in an early step of the API transport, after its assembly into dodecamers. Because Yo1082p fulfills the functional requisites that define the CVT proteins, we propose to name it Cvt19.This work was supported by Grant FMRX-CT96-0058 from the European Community (to I. V. S. and M. J. M.) and by grants from the Comisión Interministerial de Ciencia y Tecnología (94-0035 (to I. V. S.)) and the Fondo de Investigaciones Sanitarias (98/279) and the Dirección General de Enseñanza Superior e Investigación Científica (PB97-0054 (to M. J. M.)).Peer Reviewe