SDB 2011: Sperm & epithelia & chromatin

What makes a plenary session different from the other sessions here? I don’t know.

10:00-11:30 Session 6: Plenary Session (Chair: Marian Waterman [UC Irvine])

  10:00-10:30 Wei Yan (Univ. of Nevada) “The control of cytoplasm removal during late spermiogenesis”

I produced 100,000 sperm in the time it took him to say his first sentence. I’m so proud.

Part of process of spermiogenesis is removal of cytoplasm and organelles from sperm. Found late expression of Spem1 protein in maturation process which doesn’t affect sperm numbers, but mulls strongly affect motility and sperm head morphology. They have a membranous bag bending the head. Can still produce progeny through ICSI.

  10:30-11:00 Anne Calof (UC Irvine) “Feedback, proliferation, and fate in sensory epithelium development”

All about regulation of olfactory epithelium, a proliferative neural tissue.
GDF8 aka myostatin regulates muscle proliferation. Related GDF11 is neural homolog. Where is it acting in olfactory lineages? GDF11 induces cell cycle withdrawal; GDF11 mutants have thicker olfactory epi, more actively dividing cells.

Different in retinal epithelium, where it doesn’t change proliferation, but changes relative numbers of different cel types in retina.

In olfactory epithelium, GDF11 doesn’t affect morphology either. 

  11:00-11:30 Jerry Crabtree (Stanford) “Instructive roles of ATP chromatin remodeling in early development and reprogramming”

Brg/Brm ATP dependent complexes that remodel chromatin. 13 subunits & 27 genes, 12 times larger than a nucleosome; combinatorial assembly. Brg important for activation of Oct4 in ICM and repression in TE — combinatorial properties allow different functions in different tissues. Context dependent sensitivity allows for a lot of different functions.

Someone remind me that I definitely need to read up more on these complexes…man, there are a lot of complications and permutations here.