Thesis defense of Matt Marcello

One of our own, Matt Marcello, will be presenting his thesis defense talk:

Insights into Mammalian Sperm-Egg Adhesion and Fusion from Studies of Knockout Mouse Models of Male Infertility

Friday, December 18, 2009, 2:30 P.M.
Sheldon Hall in the School of Public Health

I'll admit that is quite the shameless plug on my part, since Matt is in my lab -- but I'll be doing these announcement for all our RB trainees' defenses! (Matt is just the first since the blog started.)

December 15, 2009 meeting

Elizabeth Ables from the Drummond-Barbosa lab will be presenting. She has a picked a paper that hits on numerous hot issues in reproduction! (Heck, my fingers got tired typing the labels for this post!) This one should be interesting -- although maybe not the best one to have in advance of the holiday eating season ...

Main paper:
Starvation Protects Germline Stem Cells and Extends Reproductive Longevity in C. elegans
Angelo and Van Gilst
Science, 2009, 326:954-958

Complementary papers:
Perspective paper - "Strategies to get arrested," Science, 326:944-945
Another research paper - Two chemoreceptors mediate developmental effects of dauer pheromone in C. elegans, Kim et al., Science, 326:994-998

Elizabeth's commentary on why she picked this:
"In their publication, Angelo and Van Gilst demonstrate that C. elegans can undergo an adult reproductive diapause (ARD) in response to starvation that delays reproduction, extends lifespan, and protects germline stem cells despite overall germline atrophy. ARD thus gives starved C. elegans adults the ability to rapidly restore the number of germ cells upon reintroduction to a food source. The authors also demonstrate that a nuclear hormone receptor, nhr-49, is required for a proper ARD response. This article caught my eye because it highlights the role of endocrine signaling as an important link between diet and reproduction ... a main focus of our work in the Drummond-Barbosa Lab."

December 1, 2009 - Trainees, meet Donna Vogel of the Professional Development Office!

We'll take a break from paper presentations on December 1 and will have a special event for trainees in the reproductive biology labs (PIs welcome too!). Dr. Donna Vogel from the Professional Development Office will come to meet with us. Donna is an MD-PhD with special ties to reproductive biology. From 1987 to 2001, she was a program director in the Reproductive Sciences Branch of NICHD. (In fact, I got to know her when she was the program officer for my first NIH grant, my NRSA post-doctoral fellowship! Some of you might know or have heard of other program directors at NICHD, such as Dick Tasca, Susan Taymans, and Stuart Moss; these are people doing the sort of NIH job that Donna used to do.) Donna next worked with the NCI, with a focus on post-doctoral fellowship programs, then was Deputy Director of the Ellinson Foundation. In 2007, she came to Hopkins and back to her passion of training and mentoring, to head the PDO.

Donna will visit on December 1 to give us a taste of her take on career development, to discuss upcoming offerings of the PDO (especially a course, called Your Research Career, coming up in January), and to answer any and all questions about science, grants, NIH, career, life, and everything. This will be a great chance for trainees to meet Donna in this small, informal setting … and as she will tell you, you can never network too much! Oh, and you should also ask her about Jeopardy! – she was a contestant and made it to the Tournament of Champions!

Nov. 17, 2009 journal club

Leesa from the Drummond-Barbosa lab will be presenting (our first presenter from that lab!). And although this isn't our first presentation on the ovary, it's been a while! The last one I remember was when we hit on the ovarian germline stem cell controvery in 2006. Interestingly, we'll be coming back to one aspect of this part of ovarian biology with:

Tsc/mTORC1 signaling in oocytes governs the quiescence and activation of primordial follicles, Human Molecular Genetics, in press
Adhikari et al.

This work also has some interesting human health relevance, as Leesa's comments note ...
"A woman's reproductive lifespan is thought to be partially determined by the number of primordial follicles she has at birth. Primordial follicle are maintained in a quiescent state until puberty, at which point they begin to develop into ova and that 'biological clock' starts ticking away. Menopause occurs when the pool of follicles becomes exhausted. But what happens if the clock starts ticking too early? This paper from the Liu lab in Sweden investigates the signaling pathways necessary to maintain primordial follicles in a resting state in mice and finds that insulin and TOR signaling are both necessary, but not sufficient for this process. Over-activation of either pathway leads to premature ovarian failure, or POF. This study is of particular relevance to my work in the Drummond-Barbosa lab. A female Drosophila's reproductive lifespan is determined by how long her ovarian germline stem cells, or GSCs, can be maintained in the niche to produce eggs. Our lab has demonstrated that both insulin signaling and TOR signaling levels (both highly conserved pathways in structure and function) are required for GSC maintenance, and perturbation of either pathway leads to POF. Hope to see you there!"

Nov. 3, 2009 meeting

Becca from the Matunis lab will be presenting (12:30 in W2303 in the SPH).

Two-step oligoclonal development of male germ cells; PNAS 2009, 106:175-180
Ueno, Turnbull, and Weissman
Weissman lab profile here
Hot off the presses (FYI) - a profile on Weissman in the brand new issue of JCB

Becca's comments on this paper choice -
"This paper uses tetrachimeric mice to mark and study the development of the male germline and finds that the entire lineage is derived from a mere 4 cells. One of my projects is to characterize the primodial germ cell (PGC) to germline stem cell (GSC) transition in Drosophila embryos. It has long been known that, in Drosophila, the number of PGCs initially incorporated into the gonad is greater than the number of GSCs, suggesting that some sort of selection process occurs. This paper suggests that there are parallel themes in mammals, where germ cells that actually contribute to adult spermatogenesis also arise from a smaller, perhaps select few, cells within a pool of potential founder cells."

Oct. 20, 2009 meeting - the Y chromosome makes an appearance

Rachel from the Matunis lab will be presenting at the Oct. 20 meeting (12:30, W2303 in the SPH).

Cell, 2009, 138:855-869
Isodicentric Y chromosomes and Sex Disorders as Byproducts of Homologous Recombination that maintains Palindromes
Lange et al. (David Page lab)

This paper has also gotten a number of highlight write-ups (e.g., The Scientist, ScienceDaily). Since the RBJC blog started last year, this will be our first meeting on the Y chromosome and on science related to sex determination pathways (yay for new post labels!). This should be an interesting step back from the biology of the testis (which has been abundantly represented in papers presented) to the biology linked with the very first steps for getting the testis there in the first place. (Thanks, Rachel!)

Post script - Bonus points to Rachel for rallying through a cold, and for finding a comedienne who uses her Turner Syndrome as a focal point for her humor - "Dude, where's my chromosome?" [Who knew???]

Oct. 6, 2009 RBJC meeting

Phylis from the Matunis lab will be presenting (12:30 in Room W2303):

Molecular dissection of the male germ cell lineage identifies a putative spermatogonial stem cells in rhesus macaques
Hermann et al. (Kyle Orwig's lab), Human Reproduction, 2009, 24:1704-1716

Phylis admits that this paper does not relate to her research directly, "but I picked it because it helps shed some light in the characterization of spermatogonial stem cells in primates, in this case the rhesus macaque. Some work has already been done in rodents, goats and dogs in the identification and transplantation of their spermatogonial stem cells. In non-human primates, much remains to be learned." She'll also include a bit about her research on using cell death to disrupt the balance between the cells in the Drosophila testis niche.