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Gene expression and function

Video transcript

so what is gene expression well well it's basically the process where a gene is used to synthesize some sort of product so you'd go from a gene to a product and normally this product is a protein but sometimes you can have non protein coding genes you can create things like ribosomal RNA soul and plant issues list these out so you can either have a protein you can have ribosomal RNA joined to our RNA you can have T RNA tRNA you can also have something known as small nuclear RNA so basically you go from a gene to a product now how do we determine what the function of the gene is how do we determine if a specific gene exactly what dude what does it do well let's imagine a scenario where there's a cell and normally it's able to be able if you give it milk so let's imagine that we give it a bottle of milk we'll just draw a little a little bottle of milk it's not the not the greatest bottle in the world but let's imagine that this is a bottle milk so label that milk okay so if you give this cell milk and normally it's able to take the milk and digest it and it's able to use the milk for energy well what if we wanted to figure out okay why what gene is responsible for being able to digest milk well one thing that we can do is if we have an idea of maybe what gene it might be we can just knock out that gene so let's just imagine that there's a gene here and we imagine that this has something to do with the digestion of milk well if we knock it out and then we give milk to this cell and if it's still able to digest the milk then we know that this gene didn't really have much to do with digestion of milk but if we knock it out in the cells no longer able to digest the milk then we know that this gene hey it had something to do with the digestion of milk so this process is known as a knockout so basically you're knocking out a gene and trying to figure out what the [ __ ] with the function is of the gene so if you knock out a gene what happens to the organism so you basically create a knock out movement and study its effects so another thing you can do is something known as reverse genetics reverse genetics so here what you do is first you start with the gene and then you sequence it so you figure out what is the sequence of the gene and then what you can do is you can look for other gene sequences somewhere else in the genome that share a similar sequence so you sequence it and then you look for a homologous sequence somewhere else in the genome and if you note with that the homologous sequence does then you have a pretty good idea of what that gene might do so if you know that there's another there's this homologous sequence and wells in the genome and it codes for a specific protein then you know that the and you know the function of that protein then you know that the gene of interest might create a protein that has a similar function