These Adra2a knock-out mice exhibit a resting tachycardia significantly greater than normal and a reduced expression of the adrenergic receptor in the brain.
Dr. Brian Kobilka, Stanford University
Mice that are homozygous for the targeted mutation are viable, normal in size and do not display any gross physical or behavioral abnormalities. Expression of the receptor in the brain was significantly reduced as assessed by antagonist binding, which indicated a 90% reduction. The antagonist binding assay is not entirely specific for the receptor, as the residual 10% binding was attributable to a different subtype of receptor. Mutant mice exhibit a resting tachycardia of more than 180 beats/min greater than normal. Although mutant mice do not have elevated blood pressure, administration of the hypotensive agonist, dexmedetomidine, does not reduce blood pressure. Electrical stimulation of isolated heart atria at frequencies mimicking physiological sympathetic nerve activity results in increased release of noradrenaline at high frequencies and inhibited release at low frequencies. Noradrenaline release from isolated wildtype atria is higher at high frequencies than at low frequencies. Inhibition of neurogenic contraction response to electrical stimulation in isolated vas deferens by dexmedetomidine is reduced in the mutant.
A targeting vector containing neomycin resistance gene driven by the mouse phosphoglycerate kinase promoter and herpes simplex virus thymidine kinase gene was used to disrupt the sequence of the targeted gene encoding the third transmembrane domain. The construct was electroporated into 129X1/SvJ x 129S1/Sv derived R1 embryonic stem (ES) cells. Correctly targeted ES cells were aggregated with 8-cell FVB/N morulae. The resulting chimeric animals were backcrossed to C57BL/6 mice.
|Allele Name||targeted mutation 1, Brian K Kobilka|
|Allele Type||Targeted (Null/Knockout)|
|Allele Synonym(s)||alpha2A-; alpha2A-AR-; alpha2A-ARKO; alpha2A-KO|
|Gene Symbol and Name||Adra2a, adrenergic receptor, alpha 2a|
|Strain of Origin||(129X1/SvJ x 129S1/Sv)F1-Kitl+|
|Molecular Note||A neomycin cassette inserted into the gene by homologous recombination resulted in a premature stop codon within the third transmembrane domain. Confirmation of the targeting event was demonstrated through Southern analysis.|
|Mutations Made By|| |
Dr. Brian Kobilka, Stanford University
This strain originated on a FVB;129 background, has been backcrossed for 5 generations to C57BL/6 and may be maintained as a homozygote. Donating Investigator reports mutant mice usually have less than 6 litters and less than 6 pups per litter.
When using the α2A-AR KO mouse strain in a publication, please cite the originating article(s) and include JAX stock #004367 in your Materials and Methods section.
"MICE" means mouse strains, their progeny derived by inbreeding or crossbreeding, unmodified derivatives from mouse strains or their progeny supplied by The Jackson Laboratory ("JACKSON"). "PRODUCT(S)" means biological materials supplied by JACKSON, and their derivatives. "SERVICES" means projects conducted by JACKSON for other parties that may include but are not limited to the use of MICE or PRODUCTS. "RECIPIENT" means each recipient of MICE, PRODUCTS, or SERVICES provided by JACKSON including each institution, its employees and other researchers under its control. MICE or PRODUCTS shall not be: (i) used for any purpose other than internal research, (ii) sold or otherwise provided to any third party for any use, or (iii) provided to any agent or other third party to provide breeding or other services. Acceptance of MICE, PRODUCTS or SERVICES from JACKSON shall be deemed as agreement by RECIPIENT to these conditions, and departure from these conditions requires JACKSON’s prior written authorization.
MICE, PRODUCTS AND SERVICES ARE PROVIDED "AS IS". JACKSON EXTENDS NO WARRANTIES OF ANY KIND, EITHER EXPRESS, IMPLIED, OR STATUTORY, WITH RESPECT TO MICE, PRODUCTS OR SERVICES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, OR ANY WARRANTY OF NON-INFRINGEMENT OF ANY PATENT, TRADEMARK, OR OTHER INTELLECTUAL PROPERTY RIGHTS.
In case of dissatisfaction for a valid reason and claimed in writing by a purchaser within ninety (90) days of receipt of, PRODUCTS or SERVICES, JACKSON will, at its option, provide credit or replacement for the PRODUCT received or the SERVICES provided; JACKSON makes no other representations and this shall be the exclusive remedy of the purchaser. Please note specific policy for live mice.
Consistent with the requirement for a written understanding regarding animal care and use, the JACKSON Animal Care and Use Committee will review the animal care and use protocol(s) associated with any SERVICES to be performed at JACKSON, and JACKSON shall have ultimate responsibility and authority for the care of animals while on site or in JACKSON custody.
In no event shall JACKSON, its trustees, directors, officers, employees, and affiliates be liable for any causes of action or damages, including any direct, indirect, special, or consequential damages, arising out of the provision of MICE, PRODUCTS, or SERVICES, including economic damage or injury to property and lost profits, and including any damage arising from acts or negligence on the part of JACKSON, its agents or employees. Unless prohibited by law, in purchasing or receiving MICE, PRODUCTS, or SERVICES from JACKSON, purchaser or recipient, or any party claiming by or through them, expressly releases and discharges JACKSON from all such causes of action or damages, and further agrees to defend and indemnify JACKSON from any costs or damages arising out of any third party claims.
MICE, PRODUCTS or SERVICES are to be used in a safe manner and in accordance with all applicable governmental rules and regulations.
The foregoing represents the General Terms and Conditions applicable to JACKSON’s MICE, PRODUCTS or SERVICES. In addition, special terms and conditions of sale of certain MICE, PRODUCTS, or SERVICES may be set forth separately in JACKSON web pages, catalogs, price lists, contracts, and/or other documents, and these special terms and conditions shall also govern the sale of these MICE, PRODUCTS and SERVICES by JACKSON, and by its licensees and distributors.
Acceptance of delivery of MICE, PRODUCTS or SERVICES shall be deemed agreement to these terms and conditions. No purchase order or other document transmitted by purchaser or recipient that may modify the terms and conditions hereof, shall be in any way binding on JACKSON, and instead the terms and conditions set forth herein, including any special terms and conditions set forth separately, shall govern the sale of MICE, PRODUCTS or SERVICES by JACKSON.