Robert S. Danforth Professor of Biology{ Email Professor Cruz }

Research Areas: Reproduction and Embryogenesis in Marsupials

My current research interest is marsupial reproduction and development. The research projects currently underway in my lab concern cell lineage analysis in marsupial embryos, sperm pairing in New World marsupials, and the role of early pregnancy factor in mammalian development.

I team-teach an introductory lab-lecture course, 'Organismal Biology,' in the Fall, with Michael Moore and Jane Bennett. In this course, we concentrate on the structural and physiological features of both plants and animals that permit them to carry out the basics of living such as gas exchange, water balance, nutrition, reproduction, and development. We also take up special functions such as immunity, motility and nervous function in animals and plant defenses in plants. Our large lecture class is divided into small (<24-student) lab sections. We hold question-and-answer sessions (which meet Tue, Wed and Thu evenings) in this course, which is open to majors and non-majors alike. In addition, trained SI (Supplemental Instruction) Leaders offer 6 to 9 study sessions during evening and weekend hours for the benefit of students currently enrolled in this course. Thus we offer students (who have different learning styles) different ways of accessing course material.

Another course I teach is one on The Ethics of Biotech, with Associate Professor Joyce Babyak (Department of Religion). Limited to freshmen, this course delves into the subjects of cloning, stem cells, genetic manipulation, gene therapy, and so on. The course is a writing-intensive seminar as well as a discussion marathon. The enrollment limit is 14.

I teach Developmental Biology in the spring. This course deals with the intricacies of embryonic development (cleavage, axis formation, gastrulation, organogenesis), limb regeneration, and evolution of development ('evo-devo') at the molecular, cellular, and organismal levels. Most of the students in this course are biology or neuroscience majors, although I have had physics, art history, neuroscience, and biochemistry majors as well!

My current research students are shown in the photo below. Three of them (Niels, Ria and Vicki) are working on their honors projects. Niels is investigating gene expression patterns during trophoblast-epiblast differentiation in embryos of the laboratory opossum. Ria is studying differentiation of primordial germ cells in older opossum embryos, while Vicki is looking into the mechanisms of cell-cell and cell-zona adhesion in cleavage-stage embryos. Jeremy is investigating the genetic circuitry required to keep embryonic stem cells in their undifferentiated state. He is also in charge of our "Opossum Histology Reference Collection" project and our resident jack-of-all-trades. Marissa and Adrienne are working on a continuing project, sperm pairing in marsupials, started by a former student (Mark Sasaki, '00) in my lab. Kolleen is in charge of managing our opossum breeding program.

I also teach a course in Epigenetics and in Scanning Electron Microscopy, alternately with Developmental Biology. Epigenetics is the study of non-DNA-mediated hereditary changes, an emerging biological field I find satisfying because it has found some answers to riddles and mysteries in biology which entranced me as a college student many years ago: DNA methylation, "cytoplasmic inheritance," position-effect variegation and so on. In 2007, I supervised a Health Careers Practicum. Starting in 2008, I will be sharing the responsibility for the practicum with Carol Sedgwick, Oberlin's Health Careers Advisor. Limited to ten participants, this informal undertaking allows students to arrange an individual volunteer or pre-professional internship at a local facility (medical or dental office, health center, natural-history museum, community outreach program, retirement community). The goal is for the student to gain hands-on opportunities for interacting with professionals in careers he or she is contemplating. In addition to weekly discussions of student experiences, we also discuss relevant and timely issues in medicine (human and veterinary) and public health.

Private readings and winter-term projects make up the remainder of my teaching activities. I sponsor reading and research projects in entomology, parasitology, history of biology, philosophy of science, bioethics, and evolutionary theory.

Epigenetics Class, Fall 2007 Standing, L to R: K Markowitz, K Klingensmith, I Garcia-Grossman, M Hoselton, N Kingery, E Bors, A Sinsheimer, D Hong, K Ulmschnedier, E Francois. Seated or Reclining, L to R: M Thayer, I Nelson-King, J Tabol, T Mears-Clarke, Y Cruz, Z Lewis, J Morrison (Not in photo: N. Bantilan).

Health Careers Practicum, Fall 2007

L to R: J Pumilia, L Fink, K Plass, J-A Allen, K Oertner, C Salee, C Webb, Y Cruz, V Wang, L Robinson,
A L Ho, S Alfiler, N Schessel, T Shannon, M Malarkey, G Fardella.

Scannning Electron Microscopy, Fall 2007

Front: S Blake, A Cherry, Y Cruz, D Hong
Rear: M Wessels, M chen, A Ogilvy, J Frenkel, T Mears-Clarke
(Not in Photo: I Garcia-Grossman, B Grossman, K Muller, M Thayer)

My 'extra-curricular' activities include membership in the Society for Developmental Biology, Society for Reproduction and Fertility, and American Association for the Advancement of Science. I serve or have served as grant reviewer for the National Research Council, National Institutes of Health, National Science Foundation, and the United States Department of Agriculture. I serve as Oberlin's Convenor for the Natural Sciences. My community work in Oberlin includes volunteer work for the Tri-City Lupus Project, the Pilipino-American Association of Lorain County, and the David Love Memorial Fund.

I travel, hike and swim as much as I can. My next big trip will probably be to Kenya, with my daughter Elsa Cruz Pearson. I try to read all the books I should have read as a wannabee English and Philosophy major, and cook all the stuff I learned to in home ec class. I went to a Beatles concert in 1966. I grow flowers in my garden at home when I'm taking a break from making jewelry in my basement. I adore Rachmaninoff, Kazuo Ishiguro, Isamu Noguchi, Frank Lloyd Wright, and Sean Connery. I still dream of training as an architect. My most recent accomplishments are dog-sledding in Iceland, paragliding in New Zealand, checking out petroglyphs in Arizona, hiking in Dartmoor, and Cappadocia, and visiting Sevilla.

Recent Publications:

Cruz YP, Hickford D, Selwood L (2000) A staging scheme for assessing development in vitro development of organogenesis-stage embryos of Sminthopsis macroura (Marsupialia: Dasyuridae). J. Reprod. Fertil. 120:99-108.

Cruz YP, Selwood L, Morton H, Cavanagh AC (2001) Significance of serum early pregnancy factor concentrations during pregnancy and embryonic development in Sminthopsis macroura (Spencer) (Marsupialia: Dasyuridae). Reproduction 121:933-939.

Cruz YP (2001) A vanished human presence (book review of Man Corn: Cannibalism and Violence in the Prehistoric American Southwest by Turner CG II, Turner JA; University of Utah Press, Salt Lake City) Rev. Archaeol. 22:16-19.

Cui S, Griffith N, Nanayakkara K, Cruz Y, Selwood L (2002) Developmental targets for fertility control in the brushtail possum. Pp. 1-6 in Report of Conference held under the auspices of the National Strategy Committee for Possum & Bovine Tb Control, 2-4 April 2001, New Zealand Ministry of Agriculture and Forestry, ISBN 0-478-07652-5.

Cruz YP (2005) Revelationary biology (book review of The Second Tree: Stem Cells, Chimeras, and Quests for Immortality by Elaine Dewar; Carroll and Graf Publishers, New York. Evol. Dev. 7:490-493.

Cruz YP, Morton H, Cavanagh A, Selwood L, Pavlisin AF*, Roker L* (2005) Early pregnancy factor in marsupials. Symposium paper presented at the IX International Mammalogical Congress, Sapporo, Japan, 31 July- 5 August. (*Oberlin students)

Vitazka M, Norfolk JR, Cardenas H, Fadem BH, Cruz Y, Harder JD (2005) Progesterone receptor immunoreactivity in brains of gray short-tailed opossums during pheromonal induction of estrus. Research abstract presented at the 38th Annual Meeting of the Society for the Study of Reproduction, Ste. Foy (Quebec), Canada, 24 - 27 July.

Cruz YP, Morton H, Cavanagh AC, Selwood L, Wilson SD*, Sasaki M*. (2006) Early pregnancy factor in marsupials. Aust. J. Zool. 54: 211-215.

Vitazka, ME*, Cardenas H*, Cruz YP, Fadem BH, Norfolk JR*, Harder JD (2008) Progesterone receptor immunoreactivity in the hpyothalamus of female gray short-tailed opossums during pheromonal induction of estrus. (In revision).

B.S., 1971, University of the Philippines
M.S., 1974, University of the Philippines
Ph.D., 1982, University of California, Berkeley