• Basic biology and rearing of invertebrates with emphasis on arthopods, especially Class Insecta.
• Reproductive biology of the house cricket, Acheta domesticus.
• Studies on local parasites.
• Environmental and/or comparative physiological studies of animal systems.
• Research of physiology teaching methods.
• Ectoparasite distribution at the Nature Conservancy Nickel Preserve.
• Distribution and natural history studies of the American burying beetle, Nicrophorus americanus, at Camp Gruber Training Site.

• Molecular basis of antibiotic resistance in bacteria.

• Distribution and ecology of rare woody plants in northeastern Oklahoma.
• Use of a database for herbarium management.
• Seasonal changes in the nutritional content of native plants.
• Floristics of the Ozark Plateau of northeastern Oklahoma.

• Structure and function of nucleolar organizing regions and nucleolar
  biogenesis.
• Potential role of nucleolar organizing regions in chromosomal
  abnormalities.
• Study of satellite associations. Satellite associations are non-random
  associations among chromosomes containing nucleolar organizers.
• Molecular aspects of the aging process using model organisms.

My research interests are in the areas of ecotoxicology and aquatic ecology.

Specific research projects in my lab include:

• Nutrient dynamics of the Tenkiller Ferry Lake watershed
• Dose response modeling of local fish and invertebrates to hypoxia
• Human and environmental effects of heavy metal runoff from the Tar Creek Superfund site
• Chemical abatement of biofouling caused by zebra mussels
• Effectiveness of ion selective electrodes to determine metal concentrations from environmental samples

Motivated students with similar interests can also develop their own research project in my lab.

I am conducting a research project on the Swainson's Warbler throughout eastern Oklahoma. Swainson's Warblers are medium-sized neotropical migratory birds that are known for their extremely cryptic, skulky behaviour. You are more likely to hear their loud, ringing song than to see these brown birds in the dense, swampy thickets where they are found. They spend their winters in Jamaica and the Yucatan Penisula of Mexico, then migrate in the spring to the southeastern United States where they breed in bottomland hardwood forests. Historically, Swainson's Warblers were found throughout eastern Oklahoma, but due primarily to habitat loss/degradation are now found only in small patches of appropriate habitat.

Suggested projects:

• Protocalliphora parisitism (blood-sucking maggot).
• Habitat characteristics.
• Breeding behaviour.
• Territory size.
• Song studies.
• Life history (clutch size, incubation period, nestling period, etc.).
• Fledgling growth rates.
• Population densities.

• Please contact Dr. Sukhan for information.

My research interests are:

Aquatic ecology.

Reproductive dynamics of the endangered American burying beetle.

Stream invertebrates.

Click here to read two research articles that I have published.

Suggested projects:

• Examining invertebrate populations in streams through the seasons.
• Studying invertebrate colonization after stream disturbances.
• The use of invertebrates as bioindicators.
• The effect of siltation on stream invertebrates.
• The effect of soil texture on reproduction of the American burying beetle.
• Effects of competition on reproductive success of the American burying beetle.
• How soil moisture impacts reproductive success of the American burying beetle.
• The most effective marking system for the American burying beetle.

Cancer is a disease characterized by multiple genetic changes that give rise to unrestrained tissue growth that can interfere with normal organ function and eventually lead to death. Scientists are actively searching to understand the genetic changes that promote cancer formation in order to know how to treat and prevent cancer. A recent study identified a gene named CDC5L that is overexpressed in osteosarcoma, a malignant bone cancer. On the other hand, other studies have suggested that lowered expression of CDC5L might contribute to cellular aging or multiple sclerosis. Unfortunately, it is not well understood how CDC5L works nor how its altered expression might lead to disease, such as cancer. We utilize the fruit fly Drosophila melanogaster as a genetic system to study the function of CDC5L. We study what the consequences are on cell proliferation when CDC5L expression is altered in the developing Drosophila eye, either by overexpression of CDC5L or by RNAi knockdown. Preliminary results from my lab show that RNAi knockdown of CDC5L gives rise to abnormal eye tissue. The abnormal eye phenotypes created by RNAi or overexpression of CDC5L are also being used as a basis for a genetic screen to uncover the genes that are involved in CDC5L function. This research will help us to better understand how altered CDC5L expression might contribute to disease.

Students in my lab will be involved in projects that investigate the molecular and cellular basis of CDC5L function using a variety of techniques, including genetics, cell staining, and microscopy. Students will also have the opportunity to perform molecular cloning of CDC5L toward the production of transgenic flies. In addition to CDC5L, I have a number of other interesting disease genes and projects that may be pursued if a student is interested.

The broad objective of my research is to study proteins involved in DNA replication. DNA replication is an important step in the eukaryotic cell cycle, and accurate duplication of the genome is essential for cell viability. Failure to do so results in DNA breakage during replication and increased genome instability, which can cause cancer (Das-Bradoo and Bielinsky, 2009). It is crucial, therefore, to understand the entire process of DNA replication. My research will employ biochemical, molecular biology techniques, and genetics in the model organism, Saccharomyces cerevisiae. The roles of specific DNA replication proteins will be studied, which will help to gain a better understanding of their function.

Our main focus is on an essential DNA replication protein, known as minichrosome maintenance protein 10 (Mcm10). The evolutionary conserved Mcm10 has been implicated in both the initiation and elongation steps of DNA replication.  S. cerevisiae Mcm10 is cell cycle regulated and interacts with the catalytic subunit of polymerase (pol) alpha (a), the only enzyme capable of starting DNA replication in vivo. Furthermore, we have shown that Mcm10 is di-ubiquitinated and in its di-ubiquitinated form Mcm10 releases pol a and interacts with proliferating cell nuclear antigen (PCNA) (Das-Bradoo et al., 2006). PCNA is the processivity factor for pol delta (d) and pol epsilon (e), the polymerases that carry out the bulk DNA synthesis after pol a has started the process. Therefore, Mcm10 appears to be a key coordinator of the switch between pol a and pol d/e and is a putative target for anti-cancer therapy. 

Students in my lab will carry out experiments targeted to achieve a better understanding of Mcm10 and its modifications and their functional significance.

References
1. Das-Bradoo, S., and A.-K. Bielinsky. 2010. DNA replication and checkpoint control in S phase. Nature Education (Invited review) 3(9):50. Nature Education publishes science education resources for undergraduates http://www.nature.com/scitable

2. Das-Bradoo, S, Ricke, R and Bielinsky, AK. 2006. Interaction between PCNA and di-ubiquitinated Mcm10 is essential for cell growth in budding yeast. Mol. Cell. Biol. 26(13):4806-17.

Transgenic plant biotechnology has significantly impact on crop yields and farm income in the past. More and more genes will be discovered in the genomic and inserted into plants. Future plants will have many novel traits. My research interests focus on plant biotechnology and the use of plants for medicinal purposes.

Develop novel transgenic plants for production of recombinant clot-busting pharmaceutical proteins for acute ischemic stroke patient without increasing risk of brain bleeding (hemorrhage) and neurons damage. Every year, more than 750,000 people suffer from stroke with 150,000 leading to deaths in the United States. About 550,000 are first strokes, and 85% of which are ischemic. It is the 3rd leading cause of death in the U.S. Stroke is the major cause of serious, long-term disability with more than 4 million stroke survivors in the United States. Recently, vampire bat (Desmodus rotundus) salivary plasminogen activators (DSPAs) have been found more active than the t-PA without increasing side effects. We hypothesize that the transgenic plant system can offer the potential for rapid and economical scale-up DSPAs.

Even approaches for introduction transgenes into plants become routine, the random insertion of transgene into the plant genome generates unpredicatable outcomes for the transgene,multiple copies, varies gene expression and the screen for the good lines are labor intensive and time consuming. Final product carrying antibiotic resistance genes (selectable marker) raises transgenic plant safety concern. Those defects of the current plant transformation methods can hinder the future plant biotechnology application needs. Many studies have focused on integration of multiple genes in a single transgenic plant with selectable marker gene removal. Among those tools, application of site-specific recombination systems has demonstrated a promising technology to effectively target the foreign genes into a known site with unnecessary gene removal. Here, we use of the site-specific recombination systems to produce the maker-free transgenic plants with single copy transgene insertion.

Suggested projects:

• Mammals of the Mountain Pine Ridge, Belize, Central America.
• Science education for children, focusing on conservation of mammals.
• Behavior and husbandry of Zoo mammals.
• Deer population ecology at Sequoyah State Park, Oklahoma.
• Dwarf palmetto (Sabal minor) ecology in McCurtain County, Oklahoma.
• Conservation of coral reef ecosystem health on the Belize barrier reef.