Maria Craig

BS, James Madison University; PhD, University of Wisconsin-Madison

Dr. Craig is interested in studying a short protein molecule called LL37which has been implicated in the onset of certain autoimmune diseases. LL37 can bind to DNA and fold DNA into small packages, thus allowing DNA to enter cells by facilitating their movement across the cell membrane. A 2007 report by Lande et al.[1] in Nature suggests that LL37-mediated uptake of DNA by certain immune cells may incite an immune response to self-DNA, leading to the production of anti-DNA antibodies that are characteristic of autoimmune diseases such as systemic lupus erythematosus (SLE) and psoriasis.

Although much is known about the structure and function of LL37, the details of the binding interaction between LL37 and DNA remain to be elucidated. How does LL37 fold DNA into small packages and allow DNA to cross the cell membrane? Does LL37 recognize specific DNA sequences? How many LL37 molecules bind to DNA at one time? Dr. Craig proposes to investigate these questions by performing specific biophysical chemistry studies that are well-suited to undergraduate research. For instance, a decrease in the strength of binding of LL37 to DNA as the salt concentration is increased indicates a lack of sequence-specificity.