1,005 research outputs found
PIF4 enhances DNA binding by CDF2 to co-regulate target gene expression and promote Arabidopsis hypocotyl cell elongation
How specificity is conferred within gene regulatory networks is an important problem in biology. The basic helix–loop–helix PHYTOCHROME-INTERACTING FACTORs (PIFs) and single zinc-finger CYCLING DOF FACTORs (CDFs) mediate growth responses of Arabidopsis to light and temperature. We show that these two classes of transcription factor (TF) act cooperatively. CDF2 and PIF4 are temporally and spatially co-expressed, they interact to form a protein complex and act in the same genetic pathway to promote hypocotyl cell elongation. Furthermore, PIF4 substantially strengthens genome-wide occupancy of CDF2 at a subset of its target genes. One of these, YUCCA8, encodes an auxin biosynthesis enzyme whose transcription is increased by PIF4 and CDF2 to contribute to hypocotyl elongation. The binding sites of PIF4 and CDF2 in YUCCA8 are closely spaced, and in vitro PIF4 enhances binding of CDF2. We propose that this occurs by direct protein interaction and because PIF4 binding alters DNA conformation. Thus, we define mechanisms by which PIF and CDF TFs cooperate to achieve regulatory specificity and promote cell elongation in response to light
Correlations in intermediate-energy two-proton removal reactions
We report final-state-exclusive measurements of the light charged fragments
in coincidence with 26Ne residual nuclei following the direct two-proton
removal from a neutron-rich 28Mg secondary beam. A Dalitz-plot analysis and
comparisons with simulations show that a majority of the triple- coincidence
events with two protons display phase-space correlations consistent with the
(two-body) kinematics of a spatially-correlated pair-removal mechanism. The
fraction of such correlated events, 56(12) %, is consistent with the fraction
of the calculated cross section, 64 %, arising from spin S = 0 two-proton
configurations in the entrance-channel (shell-model) 28Mg ground state wave
function. This result promises access to an additional and more specific probe
of the spin and spatial correlations of valence nucleon pairs in exotic nuclei
produced as fast secondary beams.Comment: accepted for publication in Physical Review Letter
MicroRNA172 controls inflorescence meristem size through regulation of APETALA2 in Arabidopsis
Investigations of three, four, and five-particle exit channels of levels in light nuclei created using a 9C beam
The interactions of a E/A=70-MeV 9C beam with a Be target was used to
populate levels in Be, B, and C isotopes which undergo decay into many-particle
exit channels. The decay products were detected in the HiRA array and the level
energies were identified from their invariant mass. Correlations between the
decay products were examined to deduce the nature of the decays, specifically
to what extent all the fragments were created in one prompt step or whether the
disintegration proceeded in a sequential fashion through long-lived
intermediate states. In the latter case, information on the spin of the level
was also obtained. Of particular interest is the 5-body decay of the 8C ground
state which was found to disintegrate in two steps of two-proton decay passing
through the 6Beg.s. intermediate state. The isobaric analog of 8Cg.s. in 8B was
also found to undergo two-proton decay to the isobaric analog of 6Beg.s. in
6Li. A 9.69-MeV state in 10C was found to undergo prompt 4-body decay to the
2p+2alpha exit channel. The two protons were found to have a strong
enhancementin the diproton region and the relative energies of all four p-alpha
pairs were consistent with the 5Lig.s. resonance
Energy status-promoted growth and development of Arabidopsis require copper deficiency response transcriptional regulator SPL7
Systematic analyses of the MIR172 family members of Arabidopsis define their distinct roles in regulation of APETALA2 during floral transition
Welshness in British Wales: Negotiating national identity at the margins
Popular interpretations of national identity often focus on the unifying qualities of nationhood. However, societies frequently draw hierarchical distinctions between the people and places who are ‘most national’, and those who are ‘least national’. Little attention is paid to these marginal places within the nation and the experiences of their inhabitants. This article helps to address this by analysing the ‘less Welsh’ British Wales region of Wales, a country that has traditionally possessed a hierarchical, regionally constituted nationhood. The article studies the British Wales region both ‘from above’ – considering how some areas develop as ‘less national’ – and ‘from below’, introducing empirical ethnographic work into ‘everyday Welshness’ in this area. Whilst previous work on hierarchical nationhood focuses on how hierarchies are institutionalized by the state, this article demonstrates how people at the margins of the nation actively negotiate their place in the nation. Whilst people in this area expressed a strong Welshness, they also struggled to place themselves in the nation because they had internalized their lowly place within the national hierarchy. The article demonstrates the importance of place and social class for national identity construction and draws attention to the role of power in the discursive construction of hierarchical nationhood
Morphology and Histology of the Atlantic Bottlenose Dolphin (Tursiops truncatus) Adrenal Gland with Emphasis on the Medulla
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