The efficiency of gene knockin based on homology-directed repair (HDR) can be low, particularly in stem and primary cells. In addition, targeting a specific position in the genome can generally result in cells with untargeted insertion of the donor vector at non-specific locations or in carrying a cytoplasmic residue of the donor vector. Thus, we developed an improved method to select knocked-in cells efficiently based on donor vectors carrying double thymidine kinase of herpes simplex virus (HSV-tk) cassettes. We have published this article in Cell Reports Methods (Nakade et al., Cell Reports Methods 2023).

An interview with Dr. Mami Takasaki, a senior scientist and lab manager in our team, has been posted on the RIKEN BRC’s “Diversity Initiatives for Women’s Advancement: Interviews with Female Research Staff” page.

At the end of FY2022, trainee Shinsaku Amano (Graduate School of Pharmaceutical Sciences, Tokyo University of Science) has successfully completed his master’s degree and will be employed by a pharmaceutical-related company. We wish him all the best in his future endeavors! From FY2023, both Ms. Li “Rio” Rui and Ms. Ge Ningxin will join our laboratory as trainees in the Master’s program of the Life Innovation Degree Program at the University of Tsukuba. Let’s do our best on our research together!

We have published an article entitled “Generation of human induced pluripotent stem cell lines derived from four DiGeorge syndrome patients with 22q11.2 deletion”.Shimizu T, Matsuo-Takasaki M, Luijkx D, Takami M, Arai Y, Noguchi M, NakamuraY, Hayata T, Saito MK, Hayashi Y. Generation of human induced pluripotent stemcell lines derived from four DiGeorge syndrome patients with 22q11.2 deletion.Stem Cell Res. 2022 May;61:102744. doi: 10.1016/j.scr.2022.102744. Epub 2022 Mar 9. PMID: 35292424.

We discovered KLF4 variants which accelerate and stabilize reprogramming to pluripotency. Borisova E, Nishimura K, An Y, Takami M, Li J, Song D, Matsuo-Takasaki M, Luijkx D, Aizawa S, Kuno A, Sugihara E, Sato T, Yumoto F, Terada T, Hisatake K, Hayashi Y. Structurally-discovered KLF4 variants accelerate and stabilize reprogramming to pluripotency. iScience. 2021 Dec 21:103525. doi.org/10.1016/j.isci.2021.103525 Our study demonstrates how modifications in amino acid residues of DNA-binding domains enable next-generation reprogramming technology with engineered reprogramming factors.

We have published a research article on the generation and characterization of iPS cell lines with deleted JAG1 gene by genome editing technology. Song D, Zheng YW, Hemmi Y, An Y, Noguchi M, Nakamura Y, Oda T, Hayashi Y.Generation of human induced pluripotent stem cell lines carrying homozygous JAG1deletions. Stem Cell Res. 2021 Oct 26;57:102588. doi: 10.1016/j.scr.2021.102588.Epub ahead of print. PMID: 34736037. I’d like to thank all the co-authors.Congratulations, Song-san!

A postdoctoral fellow, Dr. Hidernori Ito, has joined our team.Welcome aboard, Ito-san! He studied vasculogenesis using mouse ES cell-derived cells and leukemia model mice previously.I hope he will carry out excellent studies here!

We have published a research article on the generation and characterization of iPS cell lines with fluorescent protein with ISL1 expression. Tsukamoto S, Nakade K, Wakabayashi T, Nakashima K, Takami M, Hemmi Y, Kuramochi Y, Shimizu T, Arai Y, Matsuo-Takasaki M, Noguchi M, Nakamura Y, Miwa Y, Hayashi Y. Generation of two ISL1-tdTomato reporter human induced pluripotent stem cell lines using CRISPR-Cas9 genome editing. Stem Cell Res. 2021 May;53:102363. doi: 10.1016/j.scr.2021.102363. Epub 2021 Apr 22. PMID: 34087992. I’d like to thank all the co-authors.Congratulations, Tsukamoto-san! We’re aiming to use these iPS cells to develop cellular assays to monitor ISL1 expression.

We have published a research article on the generation and characterization of iPS cells from adrenoleukodystrophy patients. Kuramochi Y, Awaya T, Matsuo-Takasaki M, Takami M, An Y, Li J, Hemmi Y, Wakabayashi T, Arai Y, Inoue J, Noguchi M, Nakamura Y, Asaka I, Akimoto K, Saito MK, Hayashi Y. Generation of two human induced pluripotent stem cell lines derived from two X-linked adrenoleukodystrophy patients with ABCD1 mutations. Stem Cell Res. 2021 May;53:102337. doi: 10.1016/j.scr.2021.102337. Epub 2021 Apr PMID: 33901816. I’d like to thank all the co-authors.Congratulations, Kuramochi-kun! We’re aiming to use these iPS cells to develop disease models and new therapies of adrenoleukodystrophy!