i just really enjoy thinking that i am so much the greater part “not me”…. mostly “other” which means my consciousness is probably the most dominant “me” occupying more a spiritual and extracorporeal space than a physical space – how fun is it to be “thought” occupying a mostly “microbiotic” house
find a short and sweet discourse on the importance of the microbiome here
salmonella (blue)
lactobacillus (green)
rotavirus (purple)
e coli (tan)
haha…. you think i am joking: just contemplate the desmosome
1) velcro (desomogleins desmocollins) rivet proteins with central hooks in the intercellular space
2) lapping surfaces (trilaminar membrane from two adjacent cells) penetrated by the desmogleins and desmocollins
3) intracellular lock washers (the plakoglobin and plakophilin linking to the desmogleins and desmocollins after their transmembrane pass) reinforcing the rivet body
4) suspension flexibility perpendicular to the cell membranes (desmoplakins which attach to the plakoglobin and plakophilin lock washers) absorbing both shear and
5) intermediate filament (ropes for applying resistace and tension to the desmoplakins which lie parallel to the plasmalemma NOT hairpin like most diagrams put them)
Looking further at the great publication by He, Cowan and Stokes in Science 2003, i just was surprised to see what looked like the most orderly set of dots in the intercellular space on either side of the central dense line (where the desmocollins and desmogleins are supposed to be hooking up in their “velcro-like” attachments. I did a screen print of their micrograph (top image which I did not manipulate)and pasted into photoshop to enhance the pattern with the burn tool (shown in the two bottom images) as an overlay of two separate layers of their original image. The dots and grid are so obvious as to be almost “silly” and if you don’t see what i am talking about…. check out the red dots within the grids in the two images below their micrograph. I have looked at hundreds of desmosomes…. now i have to go back and see whether any of my more opportune images show dots within the grid (which I have seen before. Here the Y and alternating pattern of the intercellular grid is very very apparent.
It is still possible i think, to have the Y formation be the most prominent, and also repeated in a very orderly fashion (one difference between what i see and what the paper above suggests… when they call the desomosomal cadherins to be in “a knot”. I don’t think disorder is part of this structure… but there rather there is an order which is just a little difficult to detect, owing to the very many angles (at a thickness of 90nm) to bisect a desmosomal spot and untying those possibilities (not to make a bad pun on their title) is not easy. U havn’t yet found a publication that speaks to anything that would make these central densities.
I know there are no mitochondria in their micrgraphs… and that is ultimately what I am curious about, but just in case you havn’t figured it out yet….. biology is totally amazing.
This is an awesome representation of the intercellular space of a desmosome (that I am not giving a classification to…. either coming, stable, or going since apparently the intercellular area undergoes ultrastructurally visible changes, namely the loss of the central dense periodicity, as they change states). The paper by He, Cowin, Stokes appears in Science linked here. Two reasons that I love but dont like this diagram. 1) it depicts exactly what can be seen with traditional transmission electron microscopy of the intercellular area of desmosomes, but 2) it doesn’t seem to ring true that the organization since a “knot” is less orderly? in my mind, more “chaotic”, and I think the electron micrographs show the intercellular organization is way more orderly than the diagram suggests. 3) the number of molecules in the colored diagram (part A as they label it) is more than I seem to see in the sections with TEM. The banding (i am guessing most agree to be desmocollins and desmogleins) is so regular, and the space between so lucent, that all the knot like other molecules are likely overrepresented.
I agree that in this particular view here there is only a tiny hint of any symmetry. I do like that the dimers that they have highlighted (one actually as a lambda, my favorite representation, and the one that fits the intercellular space-repeating order of a desmosome in many of my own electron micrographs best — lambda shapes mirrored vertically and ofset by half). There is no way here to tell if something was influencing the desmosmal structure (e.g. the presence of a very close mitochondrion, maybe participating in the formation or destruction of the desmosome in their picture). Lots of opportunity for that variability to be a part of a process influencing what is viewed as a chaotic knot which in fact was a highly organized intercellular component of the desmosome. I am linking their image to their article.
(it would indeed be fun to have access to that equipment, and knowledge of how to use it, and possess the specimens made to order, poof, all at once and with extreme precision).
This publication also shows some TEM images of desmosomes which i did some measurements with: the distances between the densities at the outer plasmalemma of both cells, and the distance between the periodicities of the central dense line of the intercellular space. All distances were similar… mean of all was about 4nm center of density to center of density. The intercellular width (from the outer plasmalemma to the adjacent cell was about 9nm. See lines from that TEM below (link to the manuscript is above).
Here is a great photo from Nature Reviews Molecular Biology. I was looking at the intermediate filaments (red) and understanding the effect of looking through 3D space, with fewer filaments on either side of the central area where the nucleus resides. There is no equivalent effect seen with the desmosomes… they only occur at the widest part of the cell….So tell me… what sense (other than the tension and arrangement of the intermediate filaments (which also are pointedly connected to the nuclear pores) do they “feel” that tells them the widest part of the cell. In stratified epithelia, there are many belts… .but this is tissue culture… only one belt.
Without question, cells in culture can sense “confluence”, but this is still a single layer, and the belt is the equator (but the shape is not spherical (haha). Awesome. Some have suggested that confluence is required for mature desomosomal appearance.
I like this, my only exception would be the use of the male gender for describing God.
Couldn’t help but post this cute image of my young grandaughter, a born scientist, showing us the inside of a mouth, both living and dead. Leopard PJs with a heart.
THIS IS THE KIND OF INFO ThAT WE ALL NEED TO SEE DAILY
Reduce, Reuse and Running
Thanks to the incredible help of all participants, the Green Team volunteers, and staff, the 2017 Flying Pig Marathon weekend of events diverted a total of 78% of waste, exceeding our 2017 goal of 75%. We were able to successfully reduce our carbon footprint in numerous ways, including recycling heatsheets into Trex decking and railing products, recycling food wrappers through TerraCycle, recycling unused medals and participate bibs, and repurposing medal ribbons as lanyards or recycled through Goodwill’s textile recycling program. Banners, discarded clothing at the start, and leftover food were all donated to local charities. By offering carpool parking, we reduced the number of cars on the road by 1,194. We also offset part of our carbon footprint by partnering with Taking Root in planting 5 trees along the Pig marathon course.
The Flying Pig Marathon is excited to announce a partnership with Melink Corporation of Milford as the “Official Sustainability Sponsor” of the 2018 marathon weekend.
“We are thrilled to have Melink join the Flying Pig in our sustainability efforts,” said Iris Simpson Bush, Executive Director. “The Pig and its year-long events have made sustainability a prime focus for a decade now, and Melink will only help continue our efforts to preserve the environment.”
I dont know exactly how to go about diagramming this…. but it seems that the filaments (no surprise should be had) are so critical…. for so much in cell function, just in orchestrating all the comings and goings of the organelles, in addition to some filaments making sure what enters the nucleus through those cute little nuclear pores and regulating the presence of mitochondria (energy, calcium, apoptotic proteins and membrane potential) at nuclear pores and at desmosomes (maybe adherens junctions as well). All in all, a highly complicated and interesting topic.
here are a couple of better diagrams i found on google
148nm from plasmalemma to mitochondrial outer membrane, they measure 63 to 84 from the outer limits of the desmosome (a hard place to judge), and they note that there is a lucent area (of about 5 nm, or half the diameter of an intermediate filament) between each of the dense lines of the intermediate filaments and the mitochodnrion.
41nm is intercellular space of the desmosome.
815nm=length of this particular desmosome (approximate).
Annulus=about 74nm of plasma membrane increased density on either side of the desmosome.
3 to 5 intermediate filaments parallel to mitochondrion and desmosome.
Schlötzer-Schrehardt et al 1990 also mention that there can be just one mitochondrion with one desmosome on one cell of the two involved, or there can be bilateral symmetry (i.e. one mitochondrion on one desmosome in each of the attached cells, or strings of desmosomes linked by one single mitochondrion…or a mirror. They show an image (below) of eight tethers, two mitochondria, five desmosomes, the latter spaced variably (they measured 50 – 350nm). They also remarked that when there were multiple tethers, that the intermediate filaments were more prominently arranged.
28nm=intercellular space of these desmosomes
113nm=mean length (n=5) of this particular desmosomal set, longest is about 168nm (that would be something less than the anticipated measurement of the diameter).
70nm from plasmalemma to mitochondrial outer membrane (mean of four measurements).
63nm=annulus
4 intermediate filaments parallel to desmosome and mitochondria in one opportune space (lower left of this micrograph).
Schlötzer-Schrehardt et al 1990 commented of the possibility of calcium being one of the reasons for such tethers. Aside from the anatomical location such a large frequency of desmites providing clues as to the energy required for rapid and frequent adjustment of the iris, and the likely stress on the cells…. the need for an energy resource is pretty obvious, as would be the need for releasing stretched areas from their bonds.
I wonder if ciliary processes represent a tissue with extraordinary desmite adaptability and pliability. I will work to produce an excel file with all the tissues I can find, and notations (or actual counts as provided in the Schlötzer-Schrehardt et al 1990 publication.