Duchenne muscular dystrophy (DMD) is a lethal muscle disease, caused by mutations in the gene encoding dystrophin, an actin-binding cytoskeletal protein. Absence of functional dystrophin results in muscle weakness and degeneration, eventually leading to cardiac and respiratory failure. Strategies to replace the missing dystrophin via gene therapy have been intensively pursued. However, the dystrophin gene is too large for current gene therapy approaches. Currently available micro-dystrophin constructs lack the actin-binding domain 2 and show decreased actin-binding affinity in vitro compared to full- length dystrophin. Thus increasing the actin-binding affinity of micro-dystrophin, using small molecules, could be a beneficial therapeutic approach. Here we have developed and validated a novel high-throughput screening (HTS) assay to discover small molecules that increase the binding affinity of dystrophin’s actin-binding domain1 (ABD1). We engineered a novel fluorescence resonance energy transfer (FRET) biosensor, consisting of the mClover3, fluorescent protein (donor) attached to the C- terminus of dystrophin ABD1, and Alexa Fluor 568 (acceptor) attached to the C-terminal cysteine of actin. We used this biosensor in small-molecule screening, using a unique high-precision, high-throughput screening (HTS) fluorescence lifetime assay, identifying several compounds from a FDA-approved library that significantly increase the binding between actin and ABD1. This HTS assay establishes feasibility for the discovery of small-molecule modulators of the actin-dystrophin interaction, with the ultimate goal of developing therapies for muscular dystrophy. 0.5 DTT. hDYS-ABD1 compound to the sensitivity of the cosedimentation assay. incubated 30 centrifuged 50K for 30 fraction of ABD1 actin quantified using SDS- and Coomassie blue staining Compound effect on ABD1 aggregation measured using a control sample lacked actin. simple linear single hyperbolic model, the maximum bound

Journal Pre-proof Enhancing interaction of actin and actin-binding domain 1 of dystrophin with modulators: toward improved gene therapy for Duchenne muscular dystrophy

Closed needle liver biopsy routinely provides 60-100 mg tissue from rhesus monkeys (Macaca mulatta). No mortality or morbidity was observed in over 400 needle biopsies during a two-year period in which some monkeys were biopsied over 30 times. Biopsy tissue was used as enzyme source in low-volume ill vitro systems for measurement of hepatic monooxygenase activity. Biopsy, using aspiration techniques [6-9], provides a rapid method for obtaining liver tissue. Such procedures are important diagnostic tools, but they have been utilized to a very limited extent in comparative toxicological studies. Risk assessments have been published elsewhere [7, 13]. Needle biopsy of rhesus monkeys has been described [2, 14]. Biochemical studies of hepatic effects of long-term, low-level chlorinated hydrocarbon exposures required continual measurement of enzyme activity. Biopsy techniques have provided tissue for biochemical and morphological aspects of this study. Methods and Materials Drugs and chemicals. Ketamine (Ketalarw, lOO mgjml, sterile saline) was obtained from Parke-Davis (Detroit, Mich.). Phosphate-buffered saline (PBS) was freshly prepared (8 g NaCl, 0.2 g KCI, 1.15 g Na,HPO., 0.2 g KH,P04 in I liter distilled water) and sterilized 1 Supported in part by National Institutes of Health (ES 00054). ,J .L.M. was a Shell Companies Foundation Fellow. Present address: Stauffer Chemical Co., Western Region Research Center, Richmond, CA 94802 (USA). 2 MILLER/GEE/KRIEGER/RuEBNER by autoclaving (20 min at 130"C). Antiseptic spray (Merthiolatew Aerosol, ACI, Floral Park, N.Y.) and other chemicals were obtained from commercial sources. Supplies and equipment. Needle assemblies [6) including skin trocar, clea ing cannula, and biopsy needle (1.9 x 70 mm) with stop device were purchased (Murray Baumgartner Surgical Instrument Co., Baltimore, Md.). A tight-fitting Rekard syringe (Medical Ind., . Deland, Fla.) was attached [8, 12). Animals. Rhesus monkeys (Macaca mulatta), 5-10 kg, were housed at California Primate Research Center (CPRC) on this campus. Constant temperature 25 ± 3"C and photoperiod 14LJIOD were maintained. Monkeys were fed Purina Monkey Chow-I 5 (Ralston Purina, SI. Louis, Mo.)and provided water ad libitum. Monkeys received regularveterinarycare. Preparation ofequipment and monkeys for biopsy. Biopsy needles and skin trocars were washed with soap, rinsed with water and 70% ethanol, and stored in cotton-stopped glass vials. Needles and trocars were sterilized no earlier than 24 h prior to use [6). Monkeys were fasted 12 h to reduce the frequency of emesis during biopsy. The right thoracic area of the anesthetized monkey was shaved and washed. The skin was wiped with dry gauze and 70% alcohol, and then sprayed with antiseptic. Sterile technique was maintained. Anesthesia. Anesthesia for closed needle biopsy has been generally discouraged [6, 8). However, we have found that ketamine (12 rug/kg, i.m.) is convenient and useful during needle biopsy [4). Under these conditions ketamine does not comprise the sensitivity of monooxygenase assays. It is important to minimize dose and to rinse liver specimens before homogenization to avoid ketamine interference. Duration of anesthesia is 15-20 min, and monkeys are usually fully conscious within 45 min. Closed needle liver biopsy procedure. This procedure has been modified from the technique of MENGHINI [6). The point of entry into the peritoneum is determined by percussion for maximum dullness of the region between the 7th and 9th thoracic ribs along the midaxillary line. Skin is perforated with the trocar. Because of the angled tip of the biopsy needle, the skin may be pulled up to ease insertion of the needle. The closed needle biopsy procedure may be divided into five separate phases (fig. I). Phase A. During this phase the needle is guided through the intercostal space without penetrating horny tissue. Contact with a rib may damage the needle. If dense tissue is penetrated, the needle should be withdrawn and replaced. After penetration of intercostal muscles, assistants support the monkey and rotate the torso from the lateral recumbent toward the prone position (fig. 2). Phase B. The needle is rotated while being pushed through the peritoneal membrane until its entry into the peritoneal cavity. Some PBS is forcefully expelled to clear the needle of muscle or connective tissue. If resistance to flow is felt, the peritoneal cavity has not been attained. Phase C. The liver is located by probing the peritoneal cavity with the needle. It is essential that probing movements be gentle and at right angles to the liver surface to avoid lacerating the visceral peritoneum. Phase D. When the liver is located, it is penetrated with a short positive thrust directed at right angles to the body wall. Moderate negative pressure is applied to the syringe to aid in removal of bioptic tissue. This pressure is maintained until the needle is withdrawn from the liver. The liver is punched three times, and then needle is withdrawn. Gauze is applied to the skin with light pressure to control superficial bleeding.

Closed Needle Liver Biopsy for Assessment of Monooxygenase Activity in Rhesus Monkeys (Macaca mulatta)<link href="#jmp01070-note-0001">1</link>

context of diet-induced obesity Authors: Anni M.Y. Zhang, Yi Han Xia, Ken H. Chu, Titine J.J. Ruiter, Jenny C.C. Yang, Jeffrey S.H. Lin, Nan Chen, Justin Chhuor, Shilpa Patil, Haoning Howard Cen, Elizabeth J. Rideout, Vincent R. Richard, David F. Schaeffer, Rene P. Zahedi, Christoph H. Borchers, James D. Johnson *, Janel L. Kopp * Affiliations: Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada; Department of Pathology and Laboratory and Medicine, University of British Columbia, Vancouver, Canada; Segal Cancer Proteomics Centre, Lady Davis Institute, Jewish General Hospital, McGill University, Montreal, Canada. Department of Internal Medicine, University of Manitoba, Winnipeg, Canada. Manitoba Centre for Proteomics and Systems Biology, Winnipeg, Canada. Gerald Bronfman Department of Oncology, Jewish General Hospital, McGill University, Montreal, Canada.

Title: Insulin receptors in pancreatic acinar cells contribute to Kras G12D -driven cancer initiation in the context of diet-induced obesity

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Journal Pre-proof Enhancing interaction of actin and actin-binding domain 1 of dystrophin with modulators: toward improved gene therapy for Duchenne muscular dystrophy

Closed Needle Liver Biopsy for Assessment of Monooxygenase Activity in Rhesus Monkeys <i>(Macaca mulatta)</i><link href="#jmp01070-note-0001"><sup>1</sup></link>

Title: Insulin receptors in pancreatic acinar cells contribute to Kras G12D -driven cancer initiation in the context of diet-induced obesity