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Yaklich, E.

Publications and source records attributed to Yaklich, E..

2 recordsLinked to original sources

Floral innovation through modifications in stem cell peptide signaling.

Understanding how evolution shapes genetic networks to create new developmental forms is a central question in biology. Asteraceae (sunflower family) comprise 10% of flowering plants and have capitula, a novel flowering shoot (inflorescence) that mimics a single flower (1, 2). During capitulum development, shoot stem cells undergo prolonged proliferation relative to other species (3, 4). Here we show that capitulum evolution paralleled decreases in CLAVATA3 peptide (CLV3p) signaling, a conserved repressor of stem cell proliferation. Asteraceae CLV3p displays reduced receptor binding and downstream transcriptional outputs. Reversion of CLV3 to a more active form impairs Asteraceae stem cell regulation and capitulum development. Lastly, we trace CLV3 evolution across the Asterales allowing inferences on capitulum evolution. Our findings reveal novel evolutionary mechanisms in plant reproduction and suggest approaches for engineering crops.

plant biology↗

Refining pairwise sequence alignments of membrane proteins by the incorporation of anchors

The alignment of primary sequences is a fundamental step in the analysis of protein structure, function, and evolution. Integral membrane proteins pose a significant challenge for such sequence alignment approaches, because their evolutionary relationships can be very remote, and because a high content of hydrophobic amino acids reduces their complexity. Frequently, biochemical or biophysical data is available that informs the optimum alignment, for example, indicating specific positions that share common functional or structural roles. Currently, if those positions are not correctly aligned by a standard pairwise alignment procedure, the incorporation of such information into the alignment is typically addressed in an ad hoc manner, with manual adjustments. However, such modifications are problematic because they reduce the robustness and reproducibility of the alignment. An alternative approach is the use of restraints, or anchors, to incorporate such position-matching explicitly during alignment. Here we introduce position anchoring in the alignment tool AlignMe as an aid to pairwise sequence alignment of membrane proteins. Applying this approach to realistic scenarios involving distantly-related and low complexity sequences, we illustrate how the addition of even a single anchor can dramatically improve the accuracy of the alignments, while maintaining the reproducibility and rigor of the overall alignment.

bioinformatics↗