"In the search for the miraculous, we find that its often right before our very eyes but we fail to see it. " - Jason L. Silva

Are these "appendages" just turbulence, low pressure regions in the cytosol from that the centriole is pumping cytosol through itself, causing low pressure whirls at the distal end, and propelling out cytosol at the proximal end, also generating rotation? The low pressure zones may accumulate EDTA or other additives to the samples which chelates cations, making the turbulence show up more in electron photographs (see Gogendeau et al, [1], or Paintrand, [2], on how EDTA influences the shape of the "appendages". )

I have developed a model for the how the centriole generates rotation that I call the turbine-pump model, and if these dark regions are "appendages", protein structures, then they add drag on the rotation of the centriole, their orientation is counter to what a molecular dynamo (see Yue Zhao's work, [3]) would have had positive selection for during its evolution, which points to the possibility that they are not appendages but rather distortions in the cytosol, a result of taking a snap-shot of the centriole that captures just a single frame of how it operates as a turbine-pump.

Synapses

1. Purification of centrosomes from mammalian cell lines (2015)

2. Centrosome organization and centriole architecture: their sensitivity to divalent cations (1992)

3. Centrosome Functions as a Molecular Dynamo in the Living Cell (2015)