Current Research Programs: Dr. Karl H Joplin joplin@etsu.edu ph 423-439-6921
CIRCADIAN RHYTHMS, ACTIVITY PATTERNS,
AND SPATIAL UTILIZATION
Well, probably not, though I have found that flies are a diverse group of organisms that have qualities that make them a good model system to study development and gene expression. The broad scope of my research is the study of environmental physiology. I study the transcriptional control of gene expression during development and to correlate these changes to cellular and physiological functions; respiration cycles during development and under stress conditions; the heat shock response; and sexual and social differences in area utilization and activity patterns.
My educational interests are currently centered around the HHMI educational grant developing SYMBIOSIS, an integrated math
and biology course for freshmen. I am the program director of this grant and
another HHMI grant funding a 30 institution consortium Quantitative Biology
Workshop for the summers of 2006 and 2007.
Molecular Aspects of Insect Development:
DIAPAUSE
Diapause is an aspect of their life cycle that insects use to survive winter conditions. As such it has similarities to other interrupted life stages such as the dauer larval stage of Caenorhabditis elegans, hibernation of vertebrates, sporulation of bacteria and yeast, seed dormancy of plants and perhaps even the Go stage of the cell cycle. The flesh fly, Sarcophaga crassipalpis, is an attractive organism for this study because the developmental decision to enter into either diapause or to continue development is a circadian-gated window that can be experimentally controlled by manipulating daylength. My research is opening new approaches to this area by identifying specific genes being expressed during diapause. The characteristics unique to the alternative developmental state of diapause (morphological stasis, increased thermotolerance, unique hormonal titers, metabolic cycles and cellular changes) are an indication that the continuous developmental program is switched off and an alternative (diapause) genetic program is initiated. I have described protein synthesis cycles occurring in phase with metabolic and juvenile hormone cycles found in diapausing pupae of Sarcophaga (Joplin and Denlinger, 1989). I used pulse-labeling and large format 2-D gel electrophoresis to demonstrate that numerous brain proteins are uniquely expressed during diapause (Joplin et al., 1990). An examination of the cellular ultrastructure of the ring gland, hormonal cells involved in the production and release of ecdysone and juvenile hormone, demonstrated a unique cellular organization during diapause (Joplin et al., 1993). Identification of these diapause-specific proteins in the brain would greatly expand the scope of research into the genetic control of not only diapause, but developmental states in general. Diapause, as an optional developmental state, is an example of a genetic response to an environmental cue that stops continual development and initiates an alternative developmental program. Conceptually this is similar to the Go state of the cell cycle. I am developing S. crassipalpis from its current status as a physiological model of diapause into a model system of developmental gene expression. We identified 4 diapause-up-regulated clones, 7 diapause-down regulated clones and 8 clones expressed equally in both (Flannagan et al. 1997). Sequencing has identified homology to stress response genes, cell cycle control genes and DNA repair genes. Further characterization of these clones to define their tissue and stage expression, and their genomic organization is an ongoing project.
We have recently
used a heterologous microarray to identify 500 candidate genes that appear to
be differentially expressed during diapause. My current students are using
RT-PCR to verify these results, identifying and isolating these genes using
RT-PCR. An additional area of interest is the involvement of the insulin
receptor and the genes in the insulin pathway in the control of both diapause
and aging. Other model systems have suggested that the insulin receptor in
involved in both systems and we are exploring its influence in our system.
Respiration in insects is an area of study that has been overlooked until recently. The development of flow through microrepirometers has shown that there are unexpected patterns in which the physiological basis is unknown. While examining the developmental pattern of respiration, we have found that there is a complex, but reproducible pattern of CO2 release. The first figure shows the CO2 given off by a single pupae over a 2 day period. Measurements were taken every second. A 2 hour pattern, starting at 0 is shown expanded in the second figure.
Quantitative analysis suggests there are 6 patterns that can be identified. We are beginning the experimental manipulations that will allow us to examine the physiological basis of this respiration pattern. We have found that heat shock has a very dramatic effect on this respiration pattern during development.
CIRCADIAN RHYTHMS,
ACTIVITY PATTERNS, AND SPATIAL UTILIZATION
How organisms utilize space and resources in their environment depends on a variety of factors. Factors that we (Dr. Darrell Moore, collaborator) are investigating are stress, sexual differences, circadian rhythms, and eusociality vs asocial behavors.
We have examined the effects of acute heat shock and cold shock treatments on the circadian activity of S. crassipalpis (Joplin and Moore, 1998). Our results demonstrate that stress can have a profound effect on the expression and response to environmental cues at the physiological level. The most recent results suggest that a higher order of activity can emerge from interactions due to increasing individual density in a chamber. This may have interesting implications for the study of social, rhythmic and chaotic behavior patterns in organisms.
Male Territoriality is another area that we have begun to examine. Recent work demonstrates that male flies distribute themselves nonrandomly to maximize the space available. This is not circadian, but appears to depend on visual cues. Females tend to be random in their use of space both in light and in the dark. Interestingly, males show a similar pattern to females, in the dark.
Organismal Response to Environmental Stress: HEAT SHOCK PROTEINS
Another aspect of my research explores the physiological trait of increased thermotolerance in diapausing pupae. This area examines the physiological changes of organisms in relation to the control of gene expression as they respond to their environment. I have established that the major stress-induced protein, hsp 70, is expressed as different isoforms during development in the brain and in other tissues, thus showing that heat shock protein expression in Sarcophaga is more complex than that described in Drosophila (Joplin and Denlinger, 1990). I've further shown that the heat shock proteins are expressed in response to recovery from cold shock in Sarcophaga and other insects (Joplin et al., 1990; Yocum, et al., 1991; Lee, et al., 1995, Joplin and Moore, 1998). Heat shock expression is an established model system of gene expression but less is known concerning its effect on the physiology of organisms during stress. Physiological responses to stress are currently being investigated using freshwater invertebrates and vertebrates as they respond to heat shock, heavy metals and organic pollutants. The physiological responses of model systems such as Sarcophaga crassipalpis as, the gypsy moth, Lymantria dispar, and the freeze tolerant goldenrod gall fly, Eurosta solidaginus are also being examined. Isolation of heat shock genes from various organisms using PCR will be used to determine their involvement in other stress responses. These genes could have potential commercial value if stress genes are induced in response to many environmental insults, such as pollution.
STUDENTS and
COLLABORATORS
Collaborators
n Dr. David L. Denlinger
n
n Dr George Yocum
n USDA
n Dr. Darrell Moore
n Dr. Hugh Miller III
Graduate Students
n Will Vogt #
n Jarrett Gregory #
n Brad Schlomer #
n Nikki Ball #
n Andrew Barker #
n Amy Robertson #
n Caleb Paquette - current
n Justin Peyton - current
# graduated
Undergraduate
Students
n *Neem Bhatt, *Abigail Mabe, Robert Morgan, *Georganna Rosel, Latasha King
*Candi Overholt, Amy Robertson, Ashan Perera
High School Students
Bryon Aragam, Jason Booton, Lisa Krekelberg
n
HHMI
n
SYMBIOSIS
n
MINIGRANT
for summer workshops
n
*Undergraduate
Research Grants
n
ETSU
RDC Grant
n
ETSU
IQB Research Stipends
n
ETSU
Summer Research Stipend - KHJ
SYMBIOSIS: An Introductory Integrated
Mathematics and Biology
Curriculum
A Howard Hughes Medical Institute (HHMI) A four year Funded Grant, 2006-2010
Grant Number #52005872 $1,700.000
Program Director: Dr. Karl H Joplin
In response to the National Research Council’s BIO2010 report urging the establishment of integration of Biology and Mathematics in undergraduate courses, faculty of the Department of Biological Sciences and the Department of Mathematics submitted the SYMBIOSIS grant to the HHMI educational agency. This was funded in 2006. We are developing a three semester course (IBMS 1100, 1200, 1300) (6 credits per semester) that integrates 3 semesters of introductory biology for majors, a semester of statistics and a semester of calculus. The courses will be team taught by a biology and a mathematic or statistics faculty. The 3 semesters will cover basic introduction to biology from a quantitative perspective, using an integrative format. The students will receive credit equivalent to BIOL 1100, 1200, 1300; MATH 1530 (Probably and Statistics) and MATH 1910 (Calculus I). A lab is included in the course consisting of both experimental and analytical components.
Bonsai is the art of growing trees in containers. The word ‘bonsai’ means plant in a pot. I am the president of the Mid Appalachian Bonsai Kai group. We have an annual bonsai exhibit in Sept. This year it will be held in the ETSU Natural History Museum at the Gray Fossil Site. I have included photos of some of my trees and the exhibits.
Knisley
J, LL Glenn, K Joplin, and P Carey. 2006. Artificial Neural Networks for
Data Mining and Feature Extraction. in Quantitative Medical Data Analysis Using
Mathematical Tools and
Statistical Techniques (D. Hong and Y. Shyr Eds.), World Scientific Publications,
Seier
E., D. Moore, and K.H. Joplin.
2002. Exploratory Tools for
Comparison of Activity Time Series. Proceedings
of the American Statistical Association, Biometrics Section [CD-ROM],
Shanks N. and K.H. Joplin. 2001. Behe, Biochemistry, and the Invisible Hand. Philo 4:53-66
Shanks N. and K.H. Joplin. 2000. Of Mousetraps and Men: Behe's biochemical
conundrum.
Shanks N and KH Joplin. 1998. Redundant Complexity: A Critical Analysis of Intelligent Design in Biochemistry. Philosophy of Science 66:268-282.
Yocum GD, KH Joplin, DL Denlinger. 1998. Developmental expression of 13 and 23 kDa small heat shock proteins in relationship to pupal diapause in the flesh fly Sarcophaga crassipalpis. Insect Biochemistry and Molecular 28:677-682.
Denlinger, DL, KH Joplin, RD Flannagan, SP
Tammariello, M-L Zhang, GD Yocum and
K-Y Lee. 1995. Diapause-specific gene expression. In: Molecular Mechanisms of Insect Metamorphosis
and Diapause. Ed. Suzuki, A., H. Kataoka and
Lee, RE Jr, RA Dommel, KH Joplin and DL Denlinger. 1995. Cryobiology of the freeze tolerant gall fly, Eurosta solidaginis: Overwintering energetics and heat shock proteins. Climate Research 5: 61-67.
Yocum GD, J Zdarek, KH Joplin, RE Lee, DC Smith, KD Manter and DL Denlinger. 1994. Alteration of eclosion rhythm and behavior by low and high temperature stress in the flesh fly, Sarcophaga crassipalpis. J. Insect Physiol. 40:13-21.
Yocum GD, J Zdarek, KH.
Yocum GD, KH Joplin and DL Denlinger. 1991. Expression of heat shock proteins in response to both heat and cold shock in diapausing pharate larvae of the gypsy moth, Lymantria dispar. Arch. of Insect Biochem. and Physiol.18:239-249.
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