Participation and Organization of General Assemble Chart, July 16, 2013

The state Senator and state Representative from each district are elected to represent constituent interests when making the laws of Iowa. Citizens can take part in the decisions made by those elected officials. For locating constituent Senators and Representatives, or to learn more about the Iowa Legislature, contact the Legislative Information Office (LIO). This document includes a organizational chart of the General Assembly.

Structural organization of alpha-subunit from purified and microsomal toad kidney (Na+ + K+)-ATPase as assessed by controlled trypsinolysis

The membrane organization of the alpha-subunit of purified (Na+ + K+)-ATPase ((Na+ + K+)-dependent adenosine triphosphate phosphorylase, EC 3.6.1.3) and of the microsomal enzyme of the kidney of the toad Bufo marinus was compared by using controlled trypsinolysis. With both enzyme preparations, digestions performed in the presence of Na+ yielded a 73 kDa fragment and in the presence of K+ a 56 kDa, a 40 kDa and small amounts of a 83 kDa fragment from the 96 kDa alpha-subunit. In contrast to mammalian preparations (Jørgensen, P.L. (1975) Biochim. Biophys. Acta 401, 399-415), trypsinolysis of the purified amphibian enzyme led to a biphasic loss of (Na+ + K+)-ATPase activity in the presence of both Na+ and K+. These data could be correlated with an early rapid cleavage of 3 kDa from the alpha-subunit in both ionic conditions and a slower degradation of the remaining 93 kDa polypeptide. On the other hand, in the microsomal enzyme, a 3 kDa shift of the alpha-subunit could only be produced in the presence of Na+. Our data indicate that (1) purification of the amphibian enzyme with detergent does not influence the overall topology of the alpha-subunit but produces a distinct structural alteration of its N-terminus and (2) the amphibian kidney enzyme responds to cations with similar conformational transitions as the mammalian kidney enzyme. In addition, anti alpha-serum used on digested enzyme samples revealed on immunoblots that the 40 kDa fragment was better recognized than the 56 kDa fragment. It is concluded that the NH2-terminal of the alpha-subunit contains more antigenic sites than the COOH-terminal domain in agreement with the results of Farley et al. (Farley, R.A., Ochoa, G.T. and Kudrow, A. (1986) Am. J. Physiol. 250, C896-C906).

Spatial organization of nucleotide excision repair proteins after UV-induced DNA damage in the human cell nucleus.

Nucleotide excision repair (NER) is an evolutionary conserved DNA repair system that is essential for the removal of UV-induced DNA damage. In this study we investigated how NER is compartmentalized in the interphase nucleus of human cells at the ultrastructural level by using electron microscopy in combination with immunogold labeling. We analyzed the role of two nuclear compartments: condensed chromatin domains and the perichromatin region. The latter contains transcriptionally active and partly decondensed chromatin at the surface of condensed chromatin domains. We studied the distribution of the damage-recognition protein XPC and of XPA, which is a central component of the chromatin-associated NER complex. Both XPC and XPA rapidly accumulate in the perichromatin region after UV irradiation, whereas only XPC is also moderately enriched in condensed chromatin domains. These observations suggest that DNA damage is detected by XPC throughout condensed chromatin domains, whereas DNA-repair complexes seem preferentially assembled in the perichromatin region. We propose that UV-damaged DNA inside condensed chromatin domains is relocated to the perichromatin region, similar to what has been shown for DNA replication. In support of this, we provide evidence that UV-damaged chromatin domains undergo expansion, which might facilitate the translocation process. Our results offer novel insight into the dynamic spatial organization of DNA repair in the human cell nucleus.

Deciphering the global organization of clustering in real complex networks

We uncover the global organization of clustering in real complex networks. To this end, we ask whether triangles in real networks organize as in maximally random graphs with given degree and clustering distributions, or as in maximally ordered graph models where triangles are forced into modules. The answer comes by way of exploring m-core landscapes, where the m-core is defined, akin to the k-core, as the maximal subgraph with edges participating in at least m triangles. This property defines a set of nested subgraphs that, contrarily to k-cores, is able to distinguish between hierarchical and modular architectures. We find that the clustering organization in real networks is neither completely random nor ordered although, surprisingly, it is more random than modular. This supports the idea that the structure of real networks may in fact be the outcome of self-organized processes based on local optimization rules, in contrast to global optimization principles.

The complex organization of human cognitive domains and their heritability: a systematic review

Una revisión sistemática de la organización compleja de los dominios cognitivos humanos y su heredabilidad. Antecedentes: se ha propuesto que la estructura de la cognición humana respondería a un sistema jerárquico, donde las secuencias propias a una acción se organizarían desde sub-unidades de análisis hasta funciones de nivel superior relativamente complejas. Esta estructura organizacional estaría reflejada en las representaciones neurales que subyacen al comportamiento humano, así como también en sus sustratos genéticos. El objetivo del presente estudio fue explorar la posible organización jerárquica de las influencias genéticas subyacentes a los dominios cognitivos humanos. Método: se revisaron treinta y cuatro estudios de la heredabilidad de la cognición en muestras de la población general, que incluyeron medidas de inteligencia, habilidades verbales y manipulativas, memoria, memoria de trabajo y velocidad de procesamiento. Resultados: diversos dominios cognitivos mostraron distintas proporciones de influencias genéticas, con las mayores estimaciones de heredabilidad halladas para las funciones cognitivas de nivel superior y las menores estimaciones para las funciones de orden medio o inferior. Conclusiones: tomando como referencia los conocimientos actuales acerca del neurodesarrollo humano, las contribuciones genéticas de las habilidades cognitivas parecen organizarse paralelamente al crecimiento ontogénico del cerebro. Se discuten estos resultados en relación a la interacción entre el control genético de las funciones cognitivas y sus influencias ambientales.

Early adversity and 5-HTT-BDNF genes: new evidences of gene-environment interactions on depressive symptoms in a general population

Adverse childhood experiences have been described as one of the major environmental risk factors for depressive disorder. Likewise, the deleterious impact of early traumatic experiences on depression seems to be moderated by individual genetic variability. Serotonin transporter (5-HTT) and the Brain-Derived Neurotrophic Factor (BDNF) seem to modulate the effect of childhood adversity on adult depression, although inconsistencies across studies have been found. Moreover, the GxE interaction concerning the different types of childhood adversity remains poorly understood. The aim of this study is to analyse the putative interaction between the 5-HTT gene (5-HTTLPR polymorphism), BDNF gene (Val66Met polymorphism) and childhood adversity in accounting for adult depressive symptoms.

Multilayered organization of jasmonate signalling in the regulation of root growth.

Physical damage can strongly affect plant growth, reducing the biomass of developing organs situated at a distance from wounds. These effects, previously studied in leaves, require the activation of jasmonate (JA) signalling. Using a novel assay involving repetitive cotyledon wounding in Arabidopsis seedlings, we uncovered a function of JA in suppressing cell division and elongation in roots. Regulatory JA signalling components were then manipulated to delineate their relative impacts on root growth. The new transcription factor mutant myc2-322B was isolated. In vitro transcription assays and whole-plant approaches revealed that myc2-322B is a dosage-dependent gain-of-function mutant that can amplify JA growth responses. Moreover, myc2-322B displayed extreme hypersensitivity to JA that totally suppressed root elongation. The mutation weakly reduced root growth in undamaged plants but, when the upstream negative regulator NINJA was genetically removed, myc2-322B powerfully repressed root growth through its effects on cell division and cell elongation. Furthermore, in a JA-deficient mutant background, ninja1 myc2-322B still repressed root elongation, indicating that it is possible to generate JA-responses in the absence of JA. We show that NINJA forms a broadly expressed regulatory layer that is required to inhibit JA signalling in the apex of roots grown under basal conditions. By contrast, MYC2, MYC3 and MYC4 displayed cell layer-specific localisations and MYC3 and MYC4 were expressed in mutually exclusive regions. In nature, growing roots are likely subjected to constant mechanical stress during soil penetration that could lead to JA production and subsequent detrimental effects on growth. Our data reveal how distinct negative regulatory layers, including both NINJA-dependent and -independent mechanisms, restrain JA responses to allow normal root growth. Mechanistic insights from this work underline the importance of mapping JA signalling components to specific cell types in order to understand and potentially engineer the growth reduction that follows physical damage.

Early adversity and 5-HTT-BDNF genes: New evidences of Gene-Environment interactions on depressive symptoms in a general population

Background Adverse childhood experiences have been described as one of the major environmental risk factors for depressive disorder. Similarly, the deleterious impact of early traumatic experiences on depression seems to be moderated by individual genetic variability. Serotonin transporter (5-HTT) and brain-derived neurotrophic factor (BDNF) modulate the effect of childhood adversity on adult depression, although inconsistencies across studies have been found. Moreover, the gene×environment (G×E) interaction concerning the different types of childhood adversity remains poorly understood. The aim of this study was to analyse the putative interaction between the 5-HTT gene (5-HTTLPR polymorphism), the BDNF gene (Val66Met polymorphism) and childhood adversity in accounting for adult depressive symptoms. Method A sample of 534 healthy individuals filled in self-report questionnaires of depressive symptomatology [the Symptom Check List 90 Revised (SCL-90-R)] and different types of childhood adversities [the Childhood Trauma Questionnaire (CTQ)]. The 5-HTTLPR polymorphism (5-HTT gene) and the Val66Met polymorphism (BDNF gene) were genotyped in the whole sample. Results Total childhood adversity (β=0.27, p<0.001), childhood sexual abuse (CSA; β=0.17, p<0.001), childhood emotional abuse (β=0.27, p<0.001) and childhood emotional neglect (β=0.22, p<0.001) had an impact on adult depressive symptoms. CSA had a greater impact on depressive symptoms in Met allele carriers of the BDNF gene than in the Val/Val group (F=5.87, p<0.0001), and in S carriers of the 5-HTTLPR polymorphism (5-HTT gene) (F=5.80, p<0.0001). Conclusions Childhood adversity per se predicted higher levels of adult depressive symptoms. In addition, BDNF Val66Met and 5-HTTLPR polymorphisms seemed to moderate the effect of CSA on adult depressive symptoms.

Effects of institutional environment and technology development on payment choice

The purpose of this paper is to analyze the combination of institutional factors and technology advances as determinants of payment systems choice. The theoretical set up suggests that countries entering into a new institutional environment approach accepting group attitudes towards payment choices as a consequence of institutional pressure and technology development. We apply the results of the model to 2004 European Union enlargement process. Results confirm the relevance of both institutional environment and technology development in retail payment system decisions of newly acceded countries.