Field of Science

Snippets of the beauty of sliced axonemes

Look what I found in obscure ultrastructure literature!

It's a star! (Ringo 1967 J Cell Biol)

That's a cross section through the transitional zone of the Chlamydomonas flagellum. The geometric intricacy actually comes from the need to transition from nine triplets of the basal body to the flagellum's nine doublets and a central pair (of microtubules). As evident in the figure below, this can get quite tricky:

Cross-sections through a Chlamydomonas flagellum and basal body. (Ringo 1967 J Cell Biol)

This could be inspiration to some fun baking project...

Speaking of sliced flagella, there are some more wonderful patterns hidden away in the axonemes of rather obscure 'heliozoans' (centrohelids and actinophryids):
Left: Spiral arrangement of microtubules in the axoneme of actinophryid(?) Echinosphaerium. (Jones & Taylor 1981 JCS) Right: Cross section through an axopod of Actionosphaerum (actinoprhyid) containing an axoneme in the centre. m - mitochondrion. (Tilney et al. 1961 JCB)

(axonemes are the cytoskeletal support within axopodia, the long spikey protrusions that make the creatures appear like miniature suns)

And here's one so bizarre it takes three additional diagrams to explain it:

Axoneme of Cienkowskya mereschkovskyi*, a centrohelid 'heliozoan' reportedly closely related to Heterophrys. (Febvre-Chevalier + Febvre 1984 Origins of Life)

*To the slavic ear, this sounds painfully like a masculine adjective applied to a feminine genus name...owww.

And back to basal bodies, parabasalian TEMs are a work of art in their own right. Especially from Joeniids:

Rows of basal bodies in the ciliary region of Pachyjoenia howa. (Brugerolle & Bordereau 2004 Eur J Protistol)

This has nothing to do whatsoever with neither protists nor axonemes, but rather a funky-looking reject from my research images. It's cytoplasmic GFP in a partly lysed plant cell (normally the GFP should look diffuse) Not sure why it does that though, but often lysing cells become very bright, and squashed material is lush with autofluorescence.

My favourite colour is GFP.

Real posts to come soon... still mildly overwhelmed by stuff at the moment. Currently working on gathering up literature both new and old on a supergroup that may or may not actually exist, and is a complete and total mess either way (the new 'Hacrobia'). On top of other things.

To give you an idea, the previously incertae sedis centrohelids are in it, apparently, and their older grouping, "heliozoa", has only recently been dissolved (Nikolaev et al 2004 PNAS), so what is now spread out over at least two supergroups (centrohelids in 'Hacrobia' and actinophryids in Stramenopila) used to be lumped under one category and now you might as well rip all your hair out trying to figure anything out in there. It basically means you have to deal with the damn things on a genus-by-genus, taxon-by-taxon basis. (luckily, they're really cute so it's not that bad ^^) Also, a couple extensive papers happen to be written by The One We Fear, and I'm still denying the fact I may eventually have to actually read them. Grrr. Oh, and add to that the horrible and sometimes altogether lacking availability of older literature, requiring you to assemble epic shopping lists for the inter-library loan people...

Should probably also write another sentence of that manuscript to feel as if I've done something this week. Describe a couple more figures that don't actually exist yet... wish all my control pictures didn't totally suck. Redoing experiments again to get better images of...controls. Sigh. Working on projects in two completely unrelated fields (and different buildings) is a bit draining... /rant


  1. Those are beautiful! How do you even find these 'ancient' gems? And the star.. was caught on camera by Ringo, eh? Ok ok, I'll refrain from making bad puns...

    Congratulations on your move btw, your new place looks great! I noticed nothing at all, until I wanted to comment here =).

  2. To find obscure ancient gems like these:
    1. get a job compiling and processing pretty much ALL the literature in the field for a new course + textbook
    2. enjoy reading old stuff on the side; also be obsessed with microscopy of all sorts
    3. tabbed browsing and control/command key
    4. ???
    5. profit!

    And thanks; Edward set up much of the new look, I just did the header.


Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="">FoS</a> = FoS