KO rats obtained by homologous recombination in rat ES cells

One year ago, the first KO rats were reported by Geurts et al. (Science, 2009, 325:433) , using the Zn-finger nucleases technology.  Half a year earlier, several laboratories had reported the pionner isolation of true rat embryonic stems (ES) cells, including a manuscript published by Li et al. (Cell, 2008, 135: 1299-1310), from Qi-Long Ying’s lab. Last week, this laboratory reported the generation of the first knockout rats obtained by homologous recombination in rat ES cells [Tong et al. (Nature, 2010, August 11)], thereby illustrating the power of those rat ES cells for the inactivation of a most popular locus, the P53 gene. This report demonstrates that the rat genome is amenable to the same type of genetic modifications as the mouse genome, using equivalent procedures.

ES cells set for aggregation with a mouse morula

Marina Gertsenstein (member of ISTT) and her colleagues, from the Samuel Lunenfeld Research Institute, Mount Sinai Hospital and the Toronto Centre for Phenogenomics, in Toronto (ON, Canada), have recently published a scientific article in PLoS ONE describing the efficient generation of mouse chimeras with C57BL/6N ES cells by aggregation with standard albino outbred ICR morulas. As detailed in this work, the use of chemically-defined ES cell culture medium (2i) appears to be crucial for the success of the experiment. This is an interesting development that can help the biomedical research community for the easy and rapid generation of C57BL/6N -derived chimeras at a reduced cost. It also complements the toolbox by which chimeras can be obtained with the popular C57BL/6N ES cells, used in the large-scale international consortiums (i.e. IKMC) aiming to generate systematic knock-outs of all genes in the mouse genome.

QTRN: Quebec Transgenic Research Network

The International Society for Transgenic Technologies (ISTT) has decided to co-sponsor the QTRN’s 6th Annual Symposium: Focus on new transgenic models and their phenotyping, organized by the Quebec Transgenic Research Network (QTRN), that will be held in Montreal, Quebec, Canada, on November 13, 2010.

This symposium will be co-organized by Jacinthe Sirois. ISTT already co-sponsored the most successful QTRN’s 5th Annual Symposium in 2009, devoted to Transgenesis: new developments and applications. Additional information will be provided in the symposium web site at due time.

Course and Symposium on Mouse Cryopreservation, Campinas, Brazil, November 22-26, 2010

The course on “Cryopreservation of Mouse Germoplasm” and the associated symposium on “Animal Models and Cryopreservation“, to be held in Campinas (Brazil), November 22-26, 2010, has released its new web site. These course and symposium are organized by the University of Campinas and the Multidisciplinary Center for Biological Investigation on Laboratory Animal Science, and it is co-sponsored by the International Society for Transgenic Technologies (ISTT). The ISTT Members Jorge Stzein and Martina Crispo are members of the Organizing Committee.

As it is stated in the symposium’s web page: “It is aimed to trigger the development of close cooperation between specialists from CEMIB and those from other institutions world wide, to train a group of biologists in cryopreservation and assisted reproduction techniques and to stimulate discussions to address the future needs and requirements of the Brazilian Scientific community in this area.”

SYMPOSIUM :New generation GMOs: Refinement in procedures, Helsinki 2010

The symposium on “New generation GMOs: Refinement in procedures“, chaired by Belén Pintado and Jan Bas Prins, co-sponsored by the International Society forTransgenic Technologies (ISTT), organized within the Scand-FELASA 2010 meeting “New paradigms in laboratory animal science”, was held in Helsinki (Finland), on June 14-17, 2010. The event was a great success and higlighted the importance of “promoting the activities of ISTT among scientific collectives not directly involved in transgenesis, but that have close contact with present or future individuals that may benefit from our society”, as Belen Pintado concluded in her meeting report.

Mouse chimera generated by injecting E14 ES cells into albino blastocysts (picture by Sergey Kupriyanov)

New images have been added to the ISTT collection of mouse pictures. Our colleague, Sergey Kupriyanov (The Scripps Research Institute, Mouse Genetics Core, La Jolla, CA, USA), has contributed with new pictures of beautiful “white creamy” mouse chimeras, obtained by injecting E14 ES cells into an albino blastocyst. Up to 264 pictures and 60 videos are now available from the ISTT web site, members-only section, illustrating different aspects of the generation and analysis of transgenic animals. This great multimedia resource is most appreciated for teaching and learning purposes.

The colors of mice

A new book on genetics of mouse pigmentation has been just published, entitled  ”The colors of mice: a model genetic network” by M. Lynn Lamoreux, Véronique Delmas, Lionel Larue and Dorothy C. Bennett (Wiley, 2010). According to publisher’s page, this new book “… showcases a blend of new technologies and new insights in the field of pigmentary genetics of mice, with comparative information on other animals…”

FELASA 2010, Helsinki (Finland), June 14-17

Next week, on June 14-17, will be held the FELASA 2010 meeting in Helsinki (Finland), devoted to “New Paradigms in Laboratory Animal Science”. This meeting is co-sponsored by ISTT. Current ISTT Treasurer, Belen Pintado, co-chairs a workshop on “New generation GMOs from a laboratory animal perspective“.

Genetic polymorphisms among C57BL/6 mouse inbred strains

A manuscript entitled “Genetic polymorphisms among C57BL/6 mouse inbred strains” has been just published by Esther Zurita, Mónica Chagoyen, Marta Cantero, Rosario Alonso, Anna González-Neira, Alejandro López-Jiménez, José Antonio López-Moreno, Carlisle P. Landel, Javier Benítez, Florencio Pazos and Lluís Montoliu in Transgenic Research. The Illumina® Mouse Medium Density Linkage Mapping panel, with 1,449 single nucleotide polymorphisms (SNPs), was used to genotype individuals from ten C57BL/6-related strains: C57BL/6JArc, C57BL/6J from The Jackson Lab, C57BL/6J from Crl, C57BL6/JRccHsd, C57BL/6JOlaHsd, C57BL/6JBomTac, B6(Cg)-Tyr (<c-2j>)/J, C57BL/6NCrl, C57BL/6NHsd and C57BL/6NTac. Twelve SNPs were found informative to discriminate between the “/N” and “/J”  C57BL/6 mouse substrains considered. These results will be instrumental for the correct genetic monitoring and appropriate mouse colony handling of different transgenic and knockout mice produced in distinct C57BL/6 inbred substrains. The SNP raw data are also available from the Mouse Phenome Database at Jackson Laboratory.

World Map and links to transgenic facilities from the ISTT web site

The International Society for Transgenic Technologies (ISTT) web site includes a list of transgenic laboratories and facilities located around the world. In addition, the web page now features a Google Maps script that indicates the geographical location of each of the transgenic facilities listed. If your facility is not yet included in this web page, please contact us (email: istt@transtechsociety.org) and we will include it right away. Thanks for your collaboration.