Ashbel Smith Professor of Biology
Office 3146 Mesa Building
Phone (432) 552-2268
E-mail: allen_d@utpb.edu
Degrees:
B.A. 1963: Geography, University of Oregon
M.A., 1967; Ph.D. 1970: Biology, University of Oregon.
Ph.D., University of Oregon, 1970
Ph.D. Thesis:
"Photic control of the proportions of two visual pigments in a fish."
Published in Vision Research 10: 1077-1112. Thesis Advisor: Fred W. Munz.
Employment History:
1967-69: Teaching Asst. and Research Asst., Biology, University of Oregon (Eugene, OR).
1968-70: U.S.P.H.S. Trainee in Physiology, Dept. of Biology, University of Oregon (Eugene, OR). 1970-72: Post-doctoral Research Associate, Ecology & Systematics, Cornell University
1972-75: Asst. Professor, Department of Zoology, University of Michigan (Ann Arbor, MI).
1975-77: Research Associate, Department of Biology, University of Oregon (Eugene, OR).
1977-2009 At UTPB: Asst. (1977); Assoc. (1980), Full Professor (1986-) , Department of Biology.
1987: Professor in Residence, Semester in London Program, University of London, UK
1988-1995: Chair, Department of Biology, UTPB;
1995-2005: Chair, Department of Science and Mathematics, UTPB. (~20 FTE faculty)
2004-2005: Interim Chair, Dept. of Science and Mathematics, UTPB (~24 FTE faculty)
1995-2009: Ashbel Smith Professor of Biology, UTPB.
Administrative Experience (highlights):
Head of Biology Graduate Program 1977-2003; Advisor to pre-professional, elementary and secondary education majors, 1979-present; Chair, Faculty search committees; Health Professions Advisory Committee since 1985 (Chair 1989-94); Pre-medical advisor, Department of Zoology, Univ. of Michigan, 1972-75.
Chair, research seminar committee, Zoology Department, University of Michigan, 1972-74; Chair, “The Fish Seminar”, Museum of Zoology, University of Michigan, 1973.
Chair of University Committees, including Animal Care, Laboratory Policy, Intellectual Property & Patent. Member of many others (e.g., safety, library, etc.). Have chaired Departmental Retention, Promotion & Tenure.
Twice elected to University Grievance Panel. Member of Faculty Senate 1980-84 (VP of Senate 1982) ,1994-96, 2003 and 2005-2009 (Chair of Senate Faculty affairs, Academic Affairs and in 2007-2009: General Education Oversight Committee.
Advisor to student Senate 1989-90. Member of teacher Education Council 1989 - 2000. University Academic Budget and Planning Subcommittee.
Academic Advising Council in 2004-2005.
Currently member of CAS Tenure and Promotion Committee.
Helped plan facilities renovation and equipment upgrade for start of freshman biology lectures and labs (1991-92), developed post-baccalaureate pre-medical program and recruitment brochure, twice organized and conceived the external review of the Department of Science and Mathematics pursuant to accreditation by the Southern Association of Colleges and Schools, as well as assessment of the Biology graduate program (MS degree), planned new BS degree in Clinical Laboratory Science (BIOL) with articulation agreements 1994, helped revise procedures for Faculty evaluation within College of Arts and Sciences, 1995.
Acted as an editor for Biology Discipline Catalog copy and introduced spreadsheet degree plans for student advising and degree checks in 1990.
Helped revise University and Departmental general education core requirements, 1991 and 1992. Served as member of the Health Careers Recruitment Committee of West Texas Rural Health Education Center (recruited local minority and disadvantaged students into health professions career tracks via summer youth health career opportunities grant – 1988-1992).
Member in 1991-93 of the steering committee for the development of the V.C. Eissler Wildlife Enhancement Area (CONOCO Oil Co.)
Active member of Habitat for Humanity since 2002.
Member of the board of Visual Assistance Network ( VAN), Midland , TX since 2008.
Member of La Mancha since its inception. Judge, Senior Division, Permian Basin Regional Science Fair.
Current Teaching:
Undergraduate: BIOL 1307:General Biology II, BIOL 4352,4151: Animal Physiology and Laboratory, BIOL 3310,3111: Invertebrate Zoology and Laboratory, UNIV 1101: Freshman Seminar, BIOL 4389: Histology All courses on WEB-CT ( on-line assisted).
Graduate: Advances in Animal Physiology (G). Neuroscience (G) Histology (G)., Photobiology.
Current Research Interest: “Evolution of the Cone Visual Cycle”.
In the vertebrates, there are two types of photoreceptors in the retina: cone photoreceptors which function at high light levels, and rods which function in dim light. Duplex retinas contain significant numbers of both rods and cones and support visual function over a 24 hour day. In both rods and cones, light isomerizes 11-cis retinal of the visual pigment to all-trans retinal which is converted to free all-trans retinol. New 11-cis retinal must be acquired to regenerate visual pigment and maintain sensitivity. It was long thought that both rods and cones acquire their 11-cis retinal from the retinal pigment epithelium (RPE), which has the necessary steps (visual cycle) to convert all-trans retinol back into 11-cis retinal. However, a new “cone visual cycle” which converts all-trans retinol into 11-cis retinol or 11-cis retinal has been detected in retinas of cone-dominant chicken and squirrels. Entirely separate from the RPE, this visual cycle is thought to reside in Muller cells of the neural retina. Its properties are such that it can maintain more rapid replacement of 11-cis retinal than the RPE-based cycle, and it appears well-adapted to maintain cone function at high light levels. Both Muller cells and cones are thought to be able to convert 11-cis retinol to 11-cis retinal, whereas rods cannot. Thus, it has been hypothesized that this visual cycle evolved in an ancestral duplex retina to 1) give cones rapid access to 11-cis retinol and/or 2) to avoid competition with rods for the 11-cis retinal supplied by the RPE.
The overall significance of this new visual cycle depends on whether it can be demonstrated in a duplex retina which is ancestral to the cone-dominant animals. Since cones evolved before rods, the cone visual cycle may have co-existed for a long time with the RPE-based rod cycle. On the other hand, it may have evolved more recently when early tetrapods confronted increased light intensities. If the cone visual cycle exists in Muller cells of a duplex retina, it would be of added value to know whether and under what conditions rods and cones exchange retinoids with the RPE and/or Muller cells. Also, the distances and contacts between the participating cells need to be established. This information is necessary for a revised understanding of cone photoreception. Thus, our goals are : 1) To ascertain the evolutionary history of the “cone visual cycle” in the vertebrates, particularly when it first evolved and whether it exists in a duplex retina. 2) To determine the degree to which cones use retinoid supplied by the Muller cell as opposed to co-utilization (with rods) of the 11-cis retinal pool from the RPE, in bright- or dim-light conditions. 3) to evaluate the diffusion path-lengths for retinoid exchange between Muller cells and cones in a duplex retina, in which photomechanical movements can be manipulate so as to increase or decrease diffusion paths between photoreceptors and either Muller cells or RPE. Projected results will produce much-needed clarification of the role of cone visual cycle in duplex retinas.
This project continues in collaboration with Dr. Andrew Tsin of UTSA. The educational impact of this study will thus include the training of students at UTPB and UTSA who will be asked to work on all phases of the project. They will learn a range of techniques including micro-technique, fluorescence microscopy, electron microscopy and retinoid biochemistry. Whether they are pursuing a baccalaureate, Master’s degree, or Ph. D. (UTSA), it is anticipated that participants will reach specific research goals by their participation in laboratory work and seminars. An ultimate goal is to facilitate entry into established post-graduate programs, and thereby contribute to the diversity within the scientific workforce of the USA.
Refereed Publications.
1. Munz, F. W. and D. M. Allen (1968). A computer assisted analysis of visual pigments. Vision Res. 8: 983-996.
2. Allen, D. M. (1971). Photic control of the proportions of two visual pigments in a fish. Vision Res. 10: 1077-1112. (Ph.D. Thesis).
3. Allen, D. M., McFarland, W. N., F. W. and H. Poston (1973). Changes in the visual pigments of trout. Canadian J. Zool. 51: 901-914.
4. Allen, D. M. and W. N. McFarland (1973). Effect of temperature on rhodopsin-porphyropsin ratios in a fish. Vision Res. 13: 1303-1309.
5. Allen, D. M. (1977). Measurements of serum thyroxine and the proportions of rhodopsin and porphyropsin in rainbow trout. Canadian J. Zool. 55: 836-842.
6. McFarland, W. N. and D. M. Allen (1977). The effects of extrinsic factors on two distinctive rhodopsin-porphyropsin systems. Canadian J. Zool. 55:1000-1009.
7. Allen, D. M. (1978). Body size and porphyropsin visual pigment in a cyprinid. Copeia 1978: 181-184.
8. Allen, D. M. and M. Cristy (1978). Thiourea does not block visual pigment responses to prolactin in a trout. Vision Research 18:859-860.
9. Allen, D. M. and J. Cooper (1979). An inexpensive reaction-time device that introduces students to the oscilloscope. American Biology Teacher 42: 67-68.
10. Allen, D. M. (1980). A device providing gradual transitions between light and dark in the animal room. Lab. Animal Sci. 4: 252-254.
11. Allen, D. M., Loew, E. R. and W. N. McFarland (1982). Seasonal change in the amount of visual pigment in the retinae of fish. Canadian J. Zool. 60: 281-287.
12. Allen, D. M. and F. W. Munz (1983). Visual pigment mixtures and the scotopic visual sensitivity in rainbow trout. Environmental Biology of Fishes 8: 185-190.
13. Rasmus, B. A. and D. M. Allen (1988). Testing new signs for biology. Sign Language Studies 60: 313-330.
14. Allen, D. M. and Foreman, M. (1994). Shedding by rod photoreceptors after sunrise in fish. Experientia 94.08: 727-732.
15. Allen, D. M. (1995). Thermal control of rod outer segment shedding in a cyprinodont fish, Fundulus zebrinus. Exp. Eye Research 61:165-171.
16. Pearson, G. A. and Allen, D. M. (1996). Vibrational communication in Eusattus convexus LeConte (Tenebrionidae: Coleoptera). Coleopterists Bulletin (in press)
17. Allen, D. M. and Hallows, T. (1997). Solar pruning of retinal rods in albino rainbow trout. VisualNeurosci 14:589-600.
18. Allen, D. M., Deramus, K., Pipes, C. and Ted Hallows. (1999). A comparison of light-induced rod degeneration in two albino teleost models. In: “Retinal Degenerative Diseases and Experimental Therapy”, Hollyfield, J. G., Anderson, R. E. and LaVail, M. M. eds.) Plenum Press, New York, pp 337-350.
19. Allen, D. M., Hendricks, G. and T. Hallows. ( 2001). Peripheral rods evade light damage in albino trout. In: “Retinal Diseases and Experimental therapy”, Anderson et al., eds; Kluwer Academic/Plenum Publishers, New York, 2001. Pages 287-300.
20. Allison, W. T., Hallows, T. E., Johnson T., Hawryshyn, C. and D. M. Allen. (2006). Photic history modifies susceptibility to retinal photo-damage in albino trout. Visual Neurosci, 23: 25-34.
21. Muniz, A., Villazana-Espinoza, E., Hatch, A, Trevino, S., Allen, D.M. and Andrew T. Tsin. (2007). Invited Review: “A novel cone cycle in the cone-dominated retina”, Experimental Eye Research, 85: 175-184).
Service to Discipline:
Member of PhD Thesis committee for Albert Munoz, UTSA Department of Life Sciences, University of Texas at San Antonio, 2004-2007.
External reviewer for Faculty Promotion, UTSA and LSUMedical Center ( New Orleans).
Service on UTPB Graduate (MS) Committees.
Manuscript reviewer for Journal of Experimental Biology (2003, 2004, 2006 and 2007 (twice), Visual Neuroscience (2006) and Ophthalmic Research (2007).
Served as a pre-reviewer for 3 other submissions in 2006.
Professional Organizations:
Texas Association of Advisors for the Health Professions (TAAHP) 1987-1997; AAAS since 1977-2003; National Association of the Deaf (NAD) 1987-95, Association for Research in Vision and Ophthalmology (ARVO - Retinal Cell Biology Section (1995- present). Member of Sigma Xi.
MS Theses Directed, 2002-2008:
1. Shelton, Lilian (2003). Photoreceptor recovery after light damage in the cichlid, Pseudochromas zebra. Ph.D. Candidate, University of Oklahoma McGee Eye Institute and ARVO participant since 2005.
4901 E. University . Odessa, Texas 79762 . (432) 552-2020