Okay, so this is actually the b panel that uses the final map of the system. The receptor expression in the olfactory is distributed different scent. But in the brain, actually, it's a magic happened to then, they can find a specific location for the targeting, okay? Okay, so this is organization of the system. So in this system, then although the signaling in the nose actually is not so clear-cut, because the receptor neuron is distributed. But in the brain, and the olfactory bulb, organized [FOREIGN] receptors [FOREIGN]. If we have a chemical coming from outside, [FOREIGN] we talk about, actually, in this neuron that express the receptors, right? And also Richard Axel and Linda Buck in 1991, they cloned the receptor gene. [FOREIGN] How can you demo straight that one? That receptor gene is really a olfactory function gene. [FOREIGN] The clone have three assumption. The three assumption, first actually, this is GPCR, should be a GPCR, okay. The second is actually, they should expressed in the nose. The certain ones, which one, do you? [FOREIGN] [FOREIGN] Okay. [FOREIGN] [FOREIGN] functionally, you've got protein to detect a chemical. [FOREIGN] detect a chemical. [FOREIGN] receptor gene. [FOREIGN] But unfortunately this receptor gene is very difficult to be expressed in the X casual sale. [FOREIGN] That's because this receptor's expression [FOREIGN] They need some maybe chaperone protein. [FOREIGN] What can you do? [FOREIGN] This is a key question and a burning question in the field. [FOREIGN] >> [INAUDIBLE] >> Okay. >> [INAUDIBLE] >> Okay. This is how to read. [FOREIGN] Odor receptor I7. [FOREIGN] Receptor, okay? [FOREIGN] Now you have the expression for this receptor, how can you check their function? [FOREIGN] O expression, you expressing more protein, right? So again, [FOREIGN] This one A is from wildcat okay? B is from this animal. And then you use the chemical to challenge to stimulate different animals. [FOREIGN] Or expression. I7 protein. Like a receptor. And then you got this extra response. [FOREIGN] 17 receptor, okay. [FOREIGN] That's a receptor gene. [FOREIGN] In the mouth, there are about 1,000 gene there. [FOREIGN] Impossible, right? [FOREIGN] These experiments only tell you those receptor gene indeed can bind to the chemical, can signal in the chemical, okay? But we don't know at all how they're signaling. The 1,000 olfactory receptor genes. [FOREIGN] To create such a odor perception with mechanism. We know the receptor is a receptor right now, okay. So there's another milestone work from Linda Buck's group in 1999. It's a sale paper. So what they did is they isolate those neuron in the nodes. [FOREIGN] Calcium sensitive dye. [FOREIGN] Okay. [FOREIGN] Chemical. [FOREIGN] To do response. [FOREIGN] Okay? And then, if you find one neuron can respond to you, some type of chemicals. That's good, you know this neuron responds to those chemicals. But you still don't know the receptor gene, right? And then you can take up, pick up the single cell to do the single cell RT-PCR. Then you can find which receptor expressed. That's what they did. What is the deal? I mean, this is stuff they are finding, okay. So the clone, they found, actually about 14 types of receptors, that means actually, for many, many cells actually, they found actually in total, they have 14. Even the type of receptors. And this is chemical stimulation. You see, one receptor can be activated by different chemicals. And one chemical can activate different receptors. This is what you talk about. [FOREIGN] So the chemical is recognized by a different compilation of the receptor neurons. Correspondently in the brain, actually it's a converter. [FOREIGN] And then glomerulus one, two, three, [FOREIGN]
