本来只有小的环化DNA才算质粒，这样很可能会被核酸酶分解的

Phttp://YGOOWEMUCKSAIQYGOW.com.EMUCCKSAI.sdfdf.me/QYGOW?EMUC.KSA
X够抠梗

瞬时转染（瞬转）细胞要通过长达几个月的筛选才能成为稳定转染（稳转）细胞～～

如果是哺乳动物细胞，还不如用慢病毒，直接基因组整合。

查了一下，找到了这段资料：
Naturally, plasmids are rare in eukaryotic cells. But plasmids carrying both promoter driving large T antigen expression and SV40 origin can replicate in mammalian cells without integration. So, if you transfect cells with pCNDA3 and select cells with G418, you may get stable cell lines with free plasmids (low copy).
As to lentivirus used in gene expression or shRNA, they are deficient virus and lack essential genes for replication and package. So, they can't complete life cycle without the assistance of helper plasmids. That's why you need packaging cells to produce infective particles.
After infection, the DNA will integrate into chromosome and replicate with host genome. This is why gene therapy with lentivirus may cause leukemia. Because the host cells harboring no helper plasmid, no infective virus will be generated.

乃应该转到小木虫。。。

酵母的可以吗？貌似pRS系列都行，然后具体拷贝数、表达什么的具体看是哪种
哺乳的话……完全不知道

貌似酵母菌……