<p>Have you ever wondered why plants never get sunburnt? This is because plants make "sunscreen" in their leaves, say researchers who claim to have finally solved the mystery after a 15-year research.<br /><br /></p>.<p>Ultra-violet rays -- the most powerful part of the sun's rays -- can damage both humans and plants. But plants rarely show signs of sun damage, despite being out in the open all day with no access to sunscreen or protective clothing.<br /><br />Now, a team at Glasgow University has found that plants have evolved a way of making their own chemical "sunscreen" within their leaves, the 'Daily Mail' reported.<br /><br />A protein in their leaves, called UVR8, actually detects the presence of UV-B rays and starts off a chemical reaction that protects the leaves.<br /><br />In their study, the researchers have revealed exactly how plants "sense" UV-B light.<br /><br />UVR8 is a "photoreceptor" -- a light detecting protein. Organisms use photoreceptors to sense particular regions of the daylight spectrum. Vertebrates, animals with backbones -- including human beings -- have photoreceptors for vision.<br /><br />Plants have photoreceptors that direct their growth towards a light source and trigger when they flower.<br /><br />The team found that UVR8 is a completely new type of photoreceptor. The protein employs specific chemicals -- "tryptophan amino acids" -- in its own structure to detect UV-B light. These amino acids very effectively sense UV-B.<br /><br />Prof Gareth Jenkins, who led the study, has described the findings, published in 'Science' journal as "groundbreaking".<br /><br />He said: "The search for this UV-B photoreceptor was something of a Holy Grail for plant photobiologists and we were very pleased last year when we discovered that UVR8 was the UV-B photoreceptor. Now, we have found that UVR8 detects UV-B by an entirely novel mechanism."</p>
<p>Have you ever wondered why plants never get sunburnt? This is because plants make "sunscreen" in their leaves, say researchers who claim to have finally solved the mystery after a 15-year research.<br /><br /></p>.<p>Ultra-violet rays -- the most powerful part of the sun's rays -- can damage both humans and plants. But plants rarely show signs of sun damage, despite being out in the open all day with no access to sunscreen or protective clothing.<br /><br />Now, a team at Glasgow University has found that plants have evolved a way of making their own chemical "sunscreen" within their leaves, the 'Daily Mail' reported.<br /><br />A protein in their leaves, called UVR8, actually detects the presence of UV-B rays and starts off a chemical reaction that protects the leaves.<br /><br />In their study, the researchers have revealed exactly how plants "sense" UV-B light.<br /><br />UVR8 is a "photoreceptor" -- a light detecting protein. Organisms use photoreceptors to sense particular regions of the daylight spectrum. Vertebrates, animals with backbones -- including human beings -- have photoreceptors for vision.<br /><br />Plants have photoreceptors that direct their growth towards a light source and trigger when they flower.<br /><br />The team found that UVR8 is a completely new type of photoreceptor. The protein employs specific chemicals -- "tryptophan amino acids" -- in its own structure to detect UV-B light. These amino acids very effectively sense UV-B.<br /><br />Prof Gareth Jenkins, who led the study, has described the findings, published in 'Science' journal as "groundbreaking".<br /><br />He said: "The search for this UV-B photoreceptor was something of a Holy Grail for plant photobiologists and we were very pleased last year when we discovered that UVR8 was the UV-B photoreceptor. Now, we have found that UVR8 detects UV-B by an entirely novel mechanism."</p>