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The selective advantage of gynomonoecy, the sexual system wherein plants produce a mixture of female and bisexual flowers, is poorly understood. One hypothesis for the evolution of this system is that the absence of androecia from female flowers reduces herbivore damage to the gynoecia of these flowers. Here, we examined patterns of herbivore damage in 53 collections representing 25 species of asters and goldenrods from Massachusetts, USA. In these taxa flowers are crowded into compact capitula, with bisexual flowers occupying the centre and female flowers situated on the periphery. Damage to gynoecia of bisexual flowers was significantly greater than damage to gynoecia of female flowers overall, and in about half of the individual populations. We also compared damage to central and peripheral flowers in the heads of 16 collections of other Asteraceae that produce only bisexual flowers to see whether the location of flowers rather than their sex might determine the patterns of herbivory. In only one of these 16 collections did we find a significant difference in herbivory between flower positions. We conclude that herbivore damage is influenced by flower type in asters and goldenrods, a pattern consistent with a role for herbivory in the evolution and maintenance of gynomonoecy. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 544-552. [ABSTRACT FROM AUTHOR]

Sts-1 is a multidomain protein that plays an important role in T-cell signaling. Sts-1 contains a ubiquitin-association (UBA) domain at the N-terminus, followed by an Src homology-3 (SH3) domain and a C-terminal domain that shares sequence homology to phosphoglycerate mutases (PGMs). The C-­terminal domain of Sts-1, Sts-1PGM, crystallizes in space group C2 with two different crystal forms. The first crystal form contains two or three Sts-1PGM molecules in the asymmetric unit and diffracts to 1.82 Å resolution, with unit-cell parameters a = 116.2, b = 74.3, c = 100.1 Å, α = γ = 90, β = 101.5°. The second crystal form contains four or six Sts-1PGM molecules in the asymmetric unit, with unit-cell parameters a = 214.9, b = 75.1, c = 116.4 Å, α = γ = 90, β = 111.6°. Greater than 95% complete native and SeMet data sets have been collected and structure determination using the multiple anomalous dispersion (MAD) technique is ongoing. [ABSTRACT FROM AUTHOR]