Dr. Mary Forrest
The study of CRIP SR/cas in Streptomyces nodosus ssp asukaensis
The restriction/modification system in prokaryotics is a well-understood mechanism that gives many species of bacteria resistance to invasion of foreign DNA, such as from plasmids or phage. The CRISPR/cas system is a more recently discovered mechanism that not only confers protection from invasion of foreign DNA’s, but also allows for an acquired immunity. The system collects short fragments of foreign DNA and incorporates them into CRISPRs (clustered regularly interspaced short palindromic repeats). These then produce short RNA molecules that direct cas proteins to recognize and bind to the foreign DNA, and either destroy it or block expression.
A CRISPR/cas system has been identified in Streptomyces coelicolor. This project will determine if a similar system exists in the related species Streptomyces nodosus ssp asukaensis.
The upregulation of the FADH2 gene to study fatty acid metabolism and its affect on inflammation in mouse cell lines
This is a recent research collaboration with Dr. Sanjoy Ghosh, Department of Biology, UBC, Okanagan campus.
Linoleic acid is an unsaturated omega-6 fatty acid found in many vegetable oils, and is considered essential to a healthy diet. However high levels of linoleic acid intake may lead to inflammation in the intestines, and possibly result in diseases such as colitis.
Once taken in by diet, linoleic acid is modified to form arachidonic acid (AA), a component of cell membranes. But AA can also be triggered to produce an inflammatory response. Another fatty acid, linolenic acid counters this effect. Linolenic acid (an omega-3 fatty acid also found in vegetable oils) produces eicosapentaenoic acid (EPA). EPA then triggers anti-inflammatory responses in cells.
These two pathways balance out in cells when there is a healthy diet, but a diet high in linoleic acid allows it to outcompete the linolenic acid and lead to inflammation. This has been seen in cell lines that are grown in the presence of excess linoleic acid.
Linoleic and linolenic acids are both first modified in the cell by being further desaturated with fatty acid desaturase 2 (FADS2). Linoleic acid outcompetes linolenic acid for the active site of this enzyme. This project tested the effect of increasing gene expression of FADS2 in a cell line to determine if a greater presence of the desaturase enzyme in the cell can counter the inflammatory effect of the linoleic acid.
Beam, J; Matier, B; Botta, A; Soliman, H; Forrest, M; Macleod, K; Ghosh, S. Dietary excess of linoleic acid alters collagen I/III ratios and stiffens the obese heart: A novel mechanism for n-6 PUFA induced cardiolipotoxicity. J Biol Chem (submitted)
The use of non-ribosomal peptides as potential antibiotics
A recent research collaboration with Dr. Paul Shipley, Chemistry/EESc Unit, and Dr. Andis Klegeris, Biology, Physical Geography Unit.
Natural products are a wide range of molecules that function as antibiotics, vitamins, toxins, etc. One MF_asukamycin_figsubgroup of these products are the non-ribosomal peptides which are produced primarily from bacteria or fungi. These peptides have many functions. Some act as immuno-suppressors, such as cyclosporin which functions in organ transplantation. Others function as antibiotics, such as gramicidin, or as antibiotic precursors for products such as penicillin or cephalosporin.
Ribosomally produced peptides are synthesized though the classic processes of transcription and translation. Non-ribosomal peptides are built by a complex of enzymes called non-ribosomal peptide synthetases or NRPSs. These complexes will catalyze the polymerization of a chain of specific amino acids to create a peptide, plus they are involved in extensive modifications within the peptides to create a huge range of unique products. Isolation of the genes coding for the NRPS enzymes would allow us to study and better understand their role in building non-ribosomal peptides. This may lead to the development of new and novel forms of antibiotics for medical purposes.
The use of BEHAB/brevican as a potential marker to study primary brain tumours
A collaboration with Dr. William McMillan, previously of the CCSI (Cancer Clinic of the Southern Interior) at KGH.
MF_RT_PCRWe received a grant from CCSI for $20,000 to study an extracellular matrix protein called BEHAB or brevican. This protein normally functions early in fetal development to aid in proper glial cell formation. It has also been found associated with primary brain tumours, or gliomas. We studied this association and the possible use of the presence of BEHAB as a marker for earlier diagnosis and treatment of gliomas. Purification of intact protein from formalin-fixed paraffin-embedded brain tissue was impossible, but we successfully isolated RNA from both ethanol-fixed and formalin-fixed paraffin-embedded samples received from CCSI. Numerous samples were tested via real-time PCR to determine the levels of gene expression. The results corresponded extremely well with tumour type and aggressiveness.
Last reviewed 10/30/2014 2:58:38 PM