Annual Grant Winners 2005-2006
Ling Li, Ph.D. – HPD College of Dental Medicine
Xudong Yuan, Ph.D. – HPD College of Pharmacy
Dean Robert Uchin, HPD College of Dental Medicine
Dean Andrés Malavé – HPD College of Pharmacy
Title: Hoxb13 Gene Silencing
by Small Interference RNA
Severe scarring is one of the most serious
complications after cleft lip and palate surgeries. Homeobox
gene Hoxb13 has been reported to play a role in scarless
wound healing process. Recent adult wound healing studies
using an adult Hoxb13 knockout mouse model indicated that
cutaneous wound healing is fetal-like with reduced scar formation.
Our long-term goal is to improve wound
healing and reduce scar formation after cleft lip surgery.
The objective of this proposed project is, primarily, to
develop a Hoxb13 gene silencing tool. It is our
central hypothesis that an optimized small interference RNA (siRNA), combined
with proper delivery tools will be able to reduce Hoxb13
gene expression, thus reducing scar formation. SiRNA oligos
are usually 19-22 base pairs in length and when introduced
into a cell, inhibit specific gene expression in a sequence-dependent
fashion. It is thus far the most effective and feasible method
in inhibiting specific gene expression.
In this study, we will
obtain an optimal siRNA oligo against Hoxb13. The Hoxb13
gene sequence will be inputted into “SiRNA Target Finder” (www.ambion.com)
which will aid in designing siRNA oligos. A Hoxb13-GFP (Green
Fluorescent Protein) fusion gene will be used as the target
to be suppressed by the siRNA oligos. Suppression of Hoxb13
gene expression will lead to the suppression of GFP expression
since it expresses as a fusion protein. Suppression activity
will be determined by the reduction in green fluorescence
and confirmed by Northern blot at the mRNA level.
we will use the biodegradable nanoparticles to deliver
siRNA. The delivery efficiency will be confirmed by fluorescence
intensity since the siRNA will be labeled with a fluorescencent
molecule. Silencing activity will be determined as described
above. In the future, we may use nanoparticles to deliver
the Hoxb13 siRNA into a dermal wounding area in situ.