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Inside six tiny pads at the end of the female gut, the cells sit where fullness and nutrients converge.<\/p>\n
Tracing that tissue, Laura Duvall at Columbia University<\/a> found the receptor in those cells and not in the brain.<\/p>\n For decades, female mosquitoes were known to lose interest in biting for several days after a blood meal, but the switch stayed hidden.<\/p>\n Pinning it to the rectum clarified where that switch sits, while leaving its signals and consequences to explain.<\/p>\n Why biting stops<\/p>\n In female Aedes aegypti \u2013 the yellow-fever mosquito<\/a> \u2013 a blood meal quiets the urge to seek humans for several days.<\/p>\n In 2019, Duvall linked that pause to NPYLR7, a receptor protein that receives appetite signals, and disabling it erased fullness.<\/p>\n The new work adds location and purpose, showing that the receptor helps turn blood nutrients into yolk for developing eggs.<\/p>\n Once that link snapped, the research stopped being only about biting and became a story about reproduction.<\/p>\n Poor egg outcomes<\/p>\n When researchers knocked out NPYLR7, the mosquitoes still drank normal blood meals and laid clutches of ordinary size.<\/p>\n Yet their eggs hatched far less reliably, and mature ovaries carried less protein, meaning the meal was not invested well.<\/p>\n Wild-type females laid about 82 eggs after full blood meals, while diluted meals cut that average to about 28.<\/p>\n Because mutants still failed after extra or diluted meals, the weak point looked like allocation, not appetite or digestion.<\/p>\n Not just waste<\/p>\n Plumbing was the obvious explanation, because the rectum normally helps insects recover water, salts, and small nutrients.<\/p>\n Across blood, saline, and sugar meals, the mutants mostly cleared food on schedule and survived the load.<\/p>\n Some mid-course delays appeared, but the meals still passed through within the expected hours or days.<\/p>\n Instead, the result narrowed the problem to signaling, pushing the story away from waste handling and toward decision-making.<\/p>\n Signals after feeding<\/p>\n Nearby nerve endings became the next suspect, because they sit close enough to talk directly with the rectal cells.<\/p>\n After a meal, those nerves release RYamide, a peptide signal from nerve cells, and the target cells answered with rising calcium.<\/p>\n Amino acids also stirred the cells, which fits the idea that they monitor both fullness and nutrient quality. <\/p>\n These responses make the rectum look less like a drain and more like a checkpoint.<\/p>\n The strange part was what these rectal cells seemed ready to send back to nearby nerves.<\/p>\n Genes active in that gut tissue pointed to vesicles<\/a>, tiny packets cells use to release signals, plus machinery for common nerve chemicals.<\/p>\n Electron microscope images then showed pools of those packets gathering after blood feeding in normal females, but not mutants.<\/p>\n Missing packets suggest the receptor helps prepare a return message, although the exact chemical signals remain unknown.<\/p>\n A cross-species clue<\/p>\n Beyond mosquitoes, animal guts often help decide when eating should slow or stop in many species.<\/p>\n In people, some weight-loss drugs<\/a> mimic a gut hormone that helps signal fullness through nerve and brain pathways.<\/p>\n Elsewhere in mammals, gut sensory cells<\/a> can synapse with nerves linked to the brain and pass nutrient information in milliseconds.<\/p>\n Even so, the parallels do not make mosquito biology the same as ours, but they strengthen the case that gut-to-brain control is ancient.<\/p>\n A target to feed<\/p>\n Control researchers care because a receptor in the gut is easier to reach than one buried in the brain.<\/p>\n Newer compounds<\/a> that activate NPYLR7 suppressed blood feeding at doses 100 times lower than earlier molecules.<\/p>\n \u201cIt\u2019s a much more accessible target than a receptor in the brain,\u201d said Duvall. <\/p>\n Still, the strategy remains early and untested outside controlled experiments, but it points toward bait-based tools that change biting behavior.<\/p>\n Controling mosquitoes through the gut<\/p>\n Important pieces are still missing, especially what signal these cells send after they sense blood-derived nutrients<\/a>.<\/p>\n The team suspects messages travel back to the nervous system, but other organs could also receive the call.<\/p>\n No one yet knows whether the same pathway operates in other blood-feeding insects or stays mostly mosquito-specific.<\/p>\n For any control strategy, those gaps remain important, since gut-based tools must work reliably outside one laboratory species.<\/p>\n A mosquito<\/a> meal now starts a signaling chain, with gut cells judging nutrients and helping decide when biting ends.<\/p>\n If scientists can tap that chain from the outside, they may gain a practical way to curb bites before they happen.<\/p>\n The study is published in Current Biology<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Scientists have identified a small cluster of cells in the mosquito gut that shuts down the urge to…\n","protected":false},"author":2,"featured_media":369853,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[103,61,60],"class_list":{"0":"post-369852","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-health","9":"tag-ie","10":"tag-ireland"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/369852","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=369852"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/369852\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/369853"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=369852"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=369852"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=369852"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"Neuropeptide](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/03\/mosquito-gut_rectal-pads_npylr7-expressing-cells_Cell_1s.webp.webp\")
<\/a>Neuropeptide Y-related pathways regulate feeding in many animals, and loss of neuropeptide Y-like receptor 7 (NPYLR7) in the mosquito gut disrupts host-seeking regulation in Aedes aegypti. Credit: Current Biology. Click image to enlarge.Mosquito gut sends messages<\/p>\n