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Este trabajo analiza las características del área y programas críticos que se implementan en el área de Recursos Humanos para DHL Panamá. Este análisis se realiza de manera investigativa a través de la visita directa a las instalaciones de DHL Panamá y una revisión de literatura sobre el área de recursos humanos y su implementación, así como referentes investigativos sobre DHL en otras regiones. Tal información se discutió con lo revelado en la visita para revelar puntos de encuentros como el empoderamiento, su énfasis en el talento, el desafío de innovación, su influencia sobre otras compañías y su potencial en formación. En conclusión, se demostró una cultura organizacional motivadora, un amplio enfoque en el desarrollo continuo y la creatividad además de su liderazgo dentro del sector. Este documento permite inspirar la posición estratégica de recursos humanos dentro de las multinacionales y sirve como guía para futuras implementaciones.

The identity of a given cell type is determined by the expression of a set of genes sharing common cis-regulatory motifs and being regulated by shared transcription factors. Here, we identify cis and trans regulatory elements that drive gene expression in the bilateral sensory neuron ASJ, located in the head of the nematode Caenorhabditis elegans. For this purpose, we have dissected the promoters of the only two genes so far reported to be exclusively expressed in ASJ, trx-1 and ssu-1. We hereby identify the ASJ motif, a functional cis-regulatory bipartite promoter region composed of two individual 6 bp elements separated by a 3 bp linker. The first element is a 6 bp CG-rich sequence that presumably binds the Sp family member zinc-finger transcription factor SPTF-1. Interestingly, within the C. elegans nervous system SPTF-1 is also found to be expressed only in ASJ neurons where it regulates expression of other genes in these neurons and ASJ cell fate. The second element of the bipartite motif is a 6 bp AT-rich sequence that is predicted to potentially bind a transcription factor of the homeobox family. Together, our findings identify a specific promoter signature and SPTF-1 as a transcription factor that functions as a terminal selector gene to regulate gene expression in C. elegans ASJ sensory neurons., Some C. elegans strains were provided by the CGC, which is funded by the National Institutes of Health Office of Research Infrastructure Programs (P40 OD010440), and by the Japanese National Bioresource Project, which is funded by the Japanese Ministry of Education, Culture, Sport, Science and Technology. We thank Nuria Flames for advice and support and María Jesús Rodríguez-Palero and Francisco José Naranjo-Galindo for excellent technical assistance. This work was financed by grants to A.M.-V. from the Junta de Andalucía (Projects P07-CVI-02697 and P08-CVI-03629). Work in the laboratory of P.S. was supported by grants from the Swedish Research Council and the Torsten Söderberg Foundation. E.K. was supported by a grant from the European Union FP6 Marie Curie Research Training Network “EUrythron” MRTN-CT-2004-005499.

Durante muchos años, el envejecimiento ha sido considerado como un proceso descontrolado de deterioro pasivo tisular que conllevaba a la muerte del organismo. Sin embargo, hoy día se sabe que el proceso de envejecimiento, al igual que otros muchos procesos biológicos, está sujeto a una estricta regulación en la que cascadas de señalización y factores de transcripción juegan un papel activo y controlado. Sorprendentemente, muchas de estas rutas están conservadas a lo largo de la evolución y gracias a organismos modelo de fácil estudio y corta vida media, como Caenorhabditis elegans, estas rutas han sido descubiertas y son en la actualidad estudiadas en detalle. En esta Tesis Doctoral nos centramos en la tiorredoxina 1 (TRX-1) de C. elegans, con expresión exclusiva en la neurona sensorial ASJ del nematodo. La ausencia de TRX-1 provoca en el animal un acortamiento de su vida media y en este estudio hemos demostrado que esta tiorredoxina juega un papel importante en la regulación de la longevidad de mutantes de algunas de las principales rutas que controlan la vida media del animal, como son la ruta de la insulina/IGF-1, de la línea germinal o de la restricción calórica. Así mismo, proponemos que TRX-1 regula la longevidad de los mutantes de estas rutas actuando en la vía de las hormonas esteroideas/DAF-12. Además, con el fin de conocer el mecanismo molecular que controla la expresión génica en la neurona ASJ de C. elegans, implicada en la regulación de la longevidad y la formación de dauer del nematodo, hemos analizado en detalle el promotor de trx-1 y ssu-1, ambos expresados exclusivamente en dicha neurona sensorial. Así, hemos podido identificar el motivo ASJ y el factor de transcripción SPTF-1 como los elementos moleculares que regulan la expresión génica en ASJ.

Trabajo presentado al 4th Spanish Worm Meeting, celebrado en Carmona (Sevilla) del 14 al 15 de marzo de 2013., Thioredoxins comprise a conserved family of proteins that mostly depend on their oxidoreductase attributes to reduce disulfide bonds in many target proteins. These redox regulators are involved in many biological processes, including stress resistance and aging. In C. elegans, thioredoxin-1 (TRX-1) is expressed specifically in the ASJ sensory neurons, which have been demonstrated to regulate both dauer formation and longevity. Indeed, we have previously reported that trx-1 (ok1449) null mutants show a decrease in their lifespan while worms overexpressing TRX-1 have a slight increase in lifespan. The reproductive system of C. elegans, among other animals, plays an important role in the regulation of lifespan. For instance, germline deficient mutants glp-1 (e2141) are long lived. In this mutant background, the FOXO transcription factor DAF-16 enters into intestinal nuclei and promotes longevity. This life span extension also requires the activity of the steroid hormone nuclear receptor DAF-12. Insulin signaling is one of the major pathways regulating longevity in all organisms. Mutations in the insulin receptor DAF-2 decrease signaling by this route, leading to the entry of DAF-16 in cell nuclei, where it activates a subset of genes that promote longevity, stress resistance and pathogen avoidance, among others. The mechanisms by which DAF-16 enters intestinal nuclei in daf-2 and glp-1 mutant backgrounds differ. Thus, kri-1, daf-9 and daf-12 are necessary for DAF-16 entry into nuclei in glp-1 mutant background, while they are not necessary for the entry in a daf-2 mutant background. trx-1 (ok1449) significantly suppresses glp-1(e2141) longevity and also suppresses nuclear localization of DAF-16 in intestinal cells but not indaf-2(m577) mutant background, indicating an essential role of trx-1 in the regulation of germ line mediated longevity. Interestingly, trx-1 (ok1449) also suppresses daf-2(e1370) and daf-2(m577) longevity. This dual function in the insulin and germ line pathways has been reported for daf-16 and also for the nuclear hormone receptor daf-12. The fact that trx-1 (ok1449) significantly decreases dauer formation in pdk-1(sa680) mutants when fed with a cholesterol-free diet, while it does not modify dauer formation in a cholesterolsupplemented diet suggests a role of trx-1 in the regulation a nuclear hormone receptor. Indeed, trx-1 (ok1449) downregulates the levels of the DAF-12 direct transcriptional target DAF-9::GFP, in a daf-2 (m577) background. Together, our data support a model where TRX-1 is regulating longevity of the insulin and germ line pathway by modulating, perhaps indirectly, DAF-12 activity.

Thioredoxins are a class of evolutionarily conserved proteins that have been demonstrated to play a key role in many cellular processes involving redox reactions. We report here the genetic and biochemical characterization of Caenorhabditis elegans TRX-3, the first metazoan thioredoxin with an intestine-specific expression pattern. By using green fluorescent protein reporters we have found that TRX-3 is expressed in both the cytoplasm and the nucleus of intestinal cells, with a prominent localization at the apical membrane. Although intestinal function, reproductive capacity, longevity, and resistance of trx-3 loss-of-function mutants to many stresses are indistinguishable from those of wild-type animals, we have observed a slight reduction in size and a minor reduction in the defecation cycle timing of trx-3 mutants. Interestingly, trx-3 is induced upon infection by Photorhabdus luminescens and Candida albicans, and TRX-3 overexpression provides a modest protection against these pathogens. Together, our data indicate that TRX-3 function in the intestine is dispensable for C. elegans development but may be important to fight specific bacterial and fungal infections., Highlights • trx-3 encodes a novel member of the thioredoxin family in Caenorhabditis elegans. • TRX-3 is the first metazoan thioredoxin specifically expressed in intestinal cells. • TRX-3 is not required for intestine development or intestinal function. • Specific bacterial and fungal infections robustly induce trx-3 expression and TRX-3 overexpression moderately protects against infection.