Compositions and methods are provided for making rat pluripotent and totipotent cells, including rat embryonic stem (ES) cells. Compositions and methods for improving efficiency or frequency of germline transmission of genetic modifications in rats are provided. Such methods and compositions comprise an in vitro culture comprising a feeder cell layer and a population of rat ES cells or a rat ES cell line, wherein the in vitro culture conditions maintain pluripotency of the ES cell and comprises a media having mouse leukemia inhibitory factor (LIF) or an active variant or fragment thereof. Various methods of establishing such rat ES cell lines are further provided. Methods of selecting genetically modified rat ES cells are also provided, along with various methods to generate a transgenic rat from the genetically modified rat ES cells provided herein. Various kits and articles of manufacture are further provided.

The invention provides methods for improving cloning efficiency and modulating an imprinting control region. In particular embodiments, the invention provides methods for activating a repressed allele within an imprinting control region, thereby treating an imprinting associated disorder. In other embodiments, the invention provides methods for improving somatic cell nuclear transfer efficiency that involve Kdm4d overexpression is a Xist knockout donor cell.

Methods and compositions are provided for assessing CRISPR/Cas-mediated non-homologous end joining (NHEJ) activity and/or CRISPR/Cas-induced recombination of a target genomic locus with an exogenous donor nucleic acid in vivo or ex vivo. The methods and compositions employ non-human animals comprising a CRISPR reporter such as a genomically integrated CRISPR reporter for detecting and measuring targeted excision of a sequence between two CRISPR/Cas nuclease cleavage sites or disruption of a sequence near a CRISPR/Cas nuclease cleavage site and/or measuring CRISPR/Cas-induced recombination of the CRISPR reporter with an exogenous donor nucleic acid to convert the coding sequence for a first reporter protein to the coding sequence for a different second reporter protein. Methods and compositions are also provided for making and using these non-human animals.

The present invention provides modified oocytes having a nuclear genome derived from a first oocyte and cytoplasm derived from a second oocyte from a different subject, and methods for making and using such modified oocytes. The methods and compositions of the present invention can be useful in a variety of settings including, but not limited to, in in vitro fertilization (IVF) procedures.

Disclosed is a composition for prevention, treatment or ameliorating of atopic dermatitis, the composition containing a monoclonal stem cell obtained via improved subfractionation culturing of a stem cell, a preparation method thereof, and a method for treating atopic dermatitis using the same. According to the improved subfractionation culturing and proliferation method of the stem cell, a desired amount of the monoclonal stem cells may be obtained in a massive manner in a short time via the rapid proliferation of the monoclonal stem cell. The monoclonal mesenchymal stem cell as obtained has an enhanced effect of treatment, prevention or ameliorating of atopic dermatitis, and thus may be usefully used for an atopic dermatitis treatment agent.

The invention provides methods for reprogramming somatic cells to generate multipotent or pluripotent cells. Such methods are useful for a variety of purposes, including treating or preventing a medical condition in an individual. The invention further provides methods for identifying an agent that reprograms somatic cells to a less differentiated state.

Provided are a method for constructing a mouse model with conditional knockout of the Tmem30a gene from a pancreatic cell and a use thereof. The construction method includes the steps of: constructing a homozygote mouse with conditional knockout of a Tmem30a gene, where both ends of one or more exons of the Tmem30a gene are inserted into directly arrayed loxp loci; and mating the mouse with a pancreatic cell specific transgenic mouse Ins2-Cre, thereby obtaining the mouse model with conditional knockout of the Tmem30a gene from the pancreatic cell. The mouse with conditional knockout of the Tmem30a gene from the pancreatic cell shows glucose intolerance and poor insulin sensitivity, and can be used as a diabetes research model.

The present invention provides a mouse with liver damage, having a high degree of damage against the mouse's original hepatocytes while having a uPA gene in a heterozygous form, and a method for efficiently preparing the mouse. Specifically, the method for preparing a mouse with liver damage having the uPA gene in a heterozygous form comprises the following steps of: (i) transforming mouse ES cells with a DNA fragment containing a liver-specific promoter/enhancer and cDNA that encodes a urokinase-type plasminogen activator operably linked under the control thereof; (ii) injecting the transformed mouse ES cells obtained in step (i) into a host embryo; (iii) transplanting the host embryo obtained in step (ii) via the injection of the ES cells into the uterus of a surrogate mother mouse, so as to obtain a chimeric mouse; and (iv) crossing the chimeric mice obtained in step (iii), so as to obtain a transgenic mouse in which the DNA fragment is introduced in a heterozygous form.

The present invention provides modified oocytes having a nuclear genome derived from a first oocyte and cytoplasm derived from a second oocyte from a different subject, and methods for making and using such modified oocytes. The methods and compositions of the present invention can be useful in a variety of settings including, but not limited to, in in vitro fertilization (IVF) procedures.

The invention provides methods for reprogramming somatic cells to generate multipotent or pluripotent cells. Such methods are useful for a variety of purposes, including treating or preventing a medical condition in an individual. The invention further provides methods for identifying an agent that reprograms somatic cells to a less differentiated state.