RESUMEN
The anterior visceral endoderm (AVE) differs from the surrounding visceral endoderm (VE) in its migratory behavior and ability to restrict primitive streak formation to the opposite side of the mouse embryo. To characterize the molecular bases for the unique properties of the AVE, we combined single-cell RNA sequencing of the VE prior to and during AVE migration with phosphoproteomics, high-resolution live-imaging, and short-term lineage labeling and intervention. This identified the transient nature of the AVE with attenuation of "anteriorizing" gene expression as cells migrate and the emergence of heterogeneities in transcriptional states relative to the AVE's position. Using cell communication analysis, we identified the requirement of semaphorin signaling for normal AVE migration. Lattice light-sheet microscopy showed that Sema6D mutants have abnormalities in basal projections and migration speed. These findings point to a tight coupling between transcriptional state and position of the AVE and identify molecular controllers of AVE migration.
RESUMEN
Diversos derivados do acido 3-fosfonopropionico foram submetidos a ensaios in vivo e in vitro, contra formas tripomastigotas da cepa Y de Trypanosoma Cruzi. Nos ensaios in vivo, realizados em camundongos previamente infectados,os derivados ensaiados se mostraram inativos, sendo que os acidos (R,S)-3-fenil-3-fosfonopropionico e (R,S)-3-fenil-3-(0,0-dietilfosfono)-propionico foram letais para alguns dos animais. Nos ensaios in vitro efetuados em cultura de tecido os compostos ensaiados foram inativos, com excecao do (R,S)-3-fenil-3-(0,0-dietilfosfono)-propionato de etila, que apresentou alguma atividade.