The embryonic shoot: a lifeline through winter

The embryonic shoot: a lifeline through winter.

The tiny vascular axis of the embryo emerges post-embryonically as an elaborate and critical infrastructure, pervading the entire plant system. Its expansive nature is especially impressive in trees, where growth and development continue for extended periods. While the shoot apical meristem (SAM) orchestrates primary morphogenesis, the vascular system is mapped out in its wake in the provascula...

Simulating winter wheat shoot apex phenology

The Arabidopsis embryonic shoot fate map.

A fate map has been constructed for the shoot apical region of the embryo of the dicotyledonous plant Arabidopsis thaliana using spontaneously arising clonal albino sectors caused by the chloroplast mutator 1-2 mutation. Chimeric seedlings exhibiting albino sectors shared between the cotyledons and first true leaves revealed patterns of organ inclusion and exclusion. Frequencies of clone sharin...

CO2 in white spruce shoot primordia entering winter dormancy

Feeding [1-C]-guanidinoacetic acid to shoot primordia, O2 uptake was inhibited and major products were C-glycine, CO2 and C-serine. The direct decarboxylation of [1-C]-guanidinoacetic acid to CO2 and N-methylguanidine, the methylation of [1-C]-guanidinoacetic acid to C-creatine, and the lytic cleavage to urea and C-glycine were all ruled out. Enzymatic transamidinations of [1-C]-guanidinoacetic...

A lifeline for primary care.

n engl j med 360;26 nejm.org june 25, 2009 2693 levels.1 Overloaded primary care practices, whose doctors are aptly compared to hamsters on a treadmill, struggle to provide prompt access and high-quality care. Three major factors contribute to this crisis. First, primary care physicians earn far lower incomes than procedural specialists, reducing career attractiveness for medical students with ...