Application of a fragment of an isolated nucleotide sequence in the construction of zebrafish without intermuscular bones. The nucleotide sequence is shown in SEQ ID NO:1. Gene mutation is performed by taking SEQ ID NO:1 as a target gene; the mutant F0 embryos are selected and cultured to adult fish; F0 mutant is hybridized with wild type zebrafish to generate an F1 embryos; sense mutant heterozygotes F1 is screened out and cultured to adult fish; and then F1 heterozygote self-crosses to generate F2 generation of three gene types, including homozygote, heterozygote, and wild type. Zebrafish without intermuscular bones is obtained by using a gene mutation method, which provided a basis for subsequent research on a molecular formation mechanism of fish intermuscular bones and the cultivation of economic fishes without intermuscular bone and possessed a basic research value and an application value in other economic aquaculture fish species.

Genetically-modified zebrafish lacking one or more immune-related genes, and the use thereof, e.g., in cell or tissue transplantation methods or in stem cell biology. Tumors, tissues, and cells originating from zebrafish, other fish species, frogs, mouse, human, or other mammals can be readily engrafted into zebrafish that lack specific immune system regulatory genes. Here, described are zebrafish in which the entire genomic regions comprising the coding sequences of genes required for the development of T, B, and NK cells (including NK-lysin expressing cells) are deleted.

A method of preparing a ddx27-deletion zebrafish mutant, including: determining a target of ddx27 knockout on a sixth exon of the ddx27 in a zebrafish and designing a gRNA sequence; using primers T7-ddx27-sfd and tracr rev for PCR amplification with a pUC19-gRNA scaffold plasmid as a template; purifying and transcribing the PCR product obtained in vitro to produce gRNA; introducing the gRNA and a Cas9 protein into the zebrafish; and culturing the zebrafish to obtain a zebrafish ddx27 mutant of stable inheritance. In addition, the application also discloses a phenotype of the ddx27-deletion zebrafish mutant, which plays an important role in investigating the biological function.

The present invention discloses methods of analyzing the immune reactive status of human tumors using zebrafish xenografts.

By analyzing the engraftment/clearance profiles in zebrafish xenografts, the present invention aims to identify new mechanisms of innate immune evasion/suppression and consequent biomarkers for immunotherapy; innate immunomodulator molecules that can be used in combination with established cancer immunotherapies, therefore engaging both arms of the immune system.

Further, the present invention allows the discovery of compounds with capacity to increase engraftment and, therefore, find immunomodulator molecules that can be used in transplantation procedures. Finally, this in vivo method will allow to select eligible patients for immunotherapy treatment.

Methods and compositions using a CRISPR-Cas Type IIIA resulting in RNA gene knockdown and knockout in an animal.

The present invention relates to transgenic ornamental barbs, as well as methods of making such fish by in vitro fertilization techniques. Also disclosed are methods of establishing a population of such transgenic barbs and methods of providing them to the ornamental fish industry for the purpose of marketing.

The present invention relates to transgenic red ornamental fish, as well as methods of making such fish by in vitro fertilization techniques. Also disclosed are methods of establishing a population of such transgenic fish and methods of providing them to the ornamental fish industry for the purpose of marketing.

The present disclosure provides a combination of antisense RNA sequences and use thereof in the production of abortive tilapia, belonging to the technical field of molecular biology and reproductive biology, the combination of antisense RNA sequences includes antisense RNA of steroidgenic factors SF1-1 and SF1-2; the nucleotide sequences of Anti-SF1-1-I, Anti-SF1-1-II, Anti-SF1-2-I and Anti-SF1-2-II are set forth in SEQ ID NO. 1-SEQ ID NO. 4 respectively. The method of the present disclosure introduces antisense RNA fragments into the eggs through the fertilization hole to realize effective and accurate targeted intervention for regulating the gene expression, and the method has the advantages of simple operation, minimal egg damage, high success rate, stable phenotype after breeding, and excellent application prospects.

The present invention relates, inter alia, to a process for making modified fish zygotes or early-stage fish embryos (particularly salmon zygotes and salmon embryos), wherein the process comprises (a) modifying the genome of the fish zygote or an early-stage fish embryo to eliminate functional expression of a germ cell survival factor gene (e.g. dead-end, dnd)\ and (b) introducing functional protein or RNA encoded by the germ cell survival factor gene into the zygote or early-stage embryo. The invention also provides fish zygotes, fish embryos, juvenile fish, mature fish and sterile fish which are produced by the processes of the invention.

A method for preparing a fish skin mucous gland bioreactor and its application, including: identifying genes specifically expressed in fish skin mucinous gland cells, promoters and secreted protein signal peptides, constructing transgenic expression vectors that can specifically express endogenous or heterologous biologically active substances in fish skin and mucous gland cells, developing stable genetic and transgenic fish that secrete bioactive substances into fish mucus, and using bioactive substances secreted by mucus glands for animal and plant growth, stress resistance and disease resistance, human health care and disease prevention, and commercial enzymes. The fish skin mucous gland bioreactor developed by the invention has the characteristics of easy breeding and expansion, more skin mucus secretion, convenient mucus collection, and easy purification of bioactive substances, and can realize the large-scale production of fish skin mucous gland bioreactor and efficient application.