The intrinsically disordered proteins belonging to the LATE EMBRYOGENESIS ABUNDANT protein (LEAP) family have been ascribed a protective function over an array of intracellular components. We focus on how LEAPs may protect a stress-susceptible proteome. These examples include instances of LEAPs providing a shield molecule function, possibly by instigating liquid-liquid phase separations. Some LEAPs bind directly to their client proteins, exerting a holdase-type chaperonin function. Finally, instances of LEAP–client protein interactions have been documented, where the LEAP modulates (interferes with) the function of the client protein, acting as a surreptitious rheostat of cellular homeostasis. From the examples identified to date, it is apparent that client protein modulation also serves to mitigate stress. While some LEAPs can physically bind and protect client proteins, some apparently bind to assist the degradation of the client proteins with which they associate. Documented instances of LEAP–client protein binding, even in the absence of stress, brings to the fore the necessity of identifying how the LEAPs are degraded post-stress to render them innocuous, a first step in understanding how the cell regulates their abundance.

In genetic improvement of the soybean crop, the selection process is complex and greatly influenced by the environment. One of the alternatives for facilitating this process is the use of selection indices, making it possible to select desirable genotypes for the early generations of breeding programs. The aim of this study was to compare different selection indices in segregating populations of soybean, indicating methods which are superior in various situations, and proposing economic weightings in order to obtain higher gains. Direct and indirect selection criteria were used, together with the classic Smith-Hazel index, an index based on the sum ranks of Mulamba and Mock, a Williams base index, an index based on the desired gains of Pesek and Baker, and a genotype-ideotype distance index. The genetic material consisted of seven F5 generation soybean populations, giving a total of 386 progeny, conducted in a Federer augmented-block design, with the following characteristics being evaluated: number of days to maturity, plant height at maturity, insertion height of the first pod, lodging, agronomic value, number of pods per plant, oil content and grain yield. According to the results, the classic index and base index showed the smallest variations in gains in the different situations and economic weightings under study. The index based on the sum of ranks using agronomic value and grain productivity as the main characteristics with an economic weighting of one, gave the most favourable gains under the conditions of this study

Nos programas de melhoramento, o processo seletivo é dificultado pela complexidade dos caracteres de expressividade econômica, em sua maioria altamente influenciados pelo ambiente. Com o auxílio de parâmetros genéticos, como a herdabilidade e o ganho com a seleção, pode-se identificar genótipos superiores em gerações precoces. O objetivo deste trabalho foi comparar diferentes critérios de seleção por meio de ganhos estimados e das progênies selecionadas, determinando os métodos superiores e os mais similares. O delineamento utilizado foi o de blocos aumentados, em que foram avaliados 1.200 genótipos, com três testemunhas intercalares. As maiores estimativas de ganhos foram obtidas pela seleção direta, porém, os índices apresentaram-se mais adequados para a seleção dos genótipos superiores por registrarem maiores ganhos totais, distribuídos entre todos os caracteres avaliados. O índice baseado em soma de "ranks" permitiu os maiores ganhos na maioria das situações analisadas.

The estimation of genetic parameters, especially in early generations, is very useful for directing the selection process in breeding programs. The present research was undertaken to estimate heritabilities in the broad sense, narrow sense and using parent-offspring regression in F3 soybean populations from six two-way crosses, originated from the Soybean Breeding Program of Faculdade de Ciências Agrárias e Veterinárias (UNESP), Jaboticabal campus. It was used the family design with common checks located ten plots apart. It was observed highly significant differences among families. The experimental coefficient of variation (CVe), the CVg/CVe ratio and the heritability showed wide variation among traits, being the highest values found for number of pods, number of seeds and grain yield, making evident the existence of variance to be exploited by breeding. The estimation of the heritability coefficients in the broad sense, narrow sense and by regression were close in most of the situations, showing that the largest part of genetic variance is of additive nature, in which simple selection methods can lead to satisfactory genetic gains.