The paradigm, still around in textbooks, that ＇in insects sex is strictly genetic, thus that they do not have sex hormones＇, is mainly based on a wrong interpretation of the ＇gynandromorph argument＇. It is no long...The paradigm, still around in textbooks, that ＇in insects sex is strictly genetic, thus that they do not have sex hormones＇, is mainly based on a wrong interpretation of the ＇gynandromorph argument＇. It is no longer tenable. Given the fact that vertebrates and invertebrates probably had a common, sexually reproducing ancestor, there is no reason to assume that only vertebrates need sex hormones. The major function of sex hormones is to inform the somatoplasm about developmental changes that take place in the gonads. In contrast to juvenile hormone and neuropeptides, ecdysteroids meet all criteria to act as sex hormones, which was probably their ancient role. Their much better documented role in moulting and metamorphosis was a secondary acquisition that enabled arthropods to cope with growth problems, imposed by a rigid cuticle. Female insects use 20-hydroxyecdysone （20E）, secreted by the follicle cells of the ovary, in a similar way as females of egg-laying vertebrates use estrogens. For a variety of reasons, the possibility that ecdysteroids, in particular ecdysone （E）, might also act as sex hormones in male insects, thus as the counterpart of testosterone of vertebrates, has been very much overlooked. Thanks to the recent discovery of the molecular basis of the haploid-diploid system of sex determination in the honeybee, the characterization of Halloween genes, proteomics, RNAi and so on, it now becomes possible to verify whether in insects, as with vertebrates, males are the endocrinologically default gender form.展开更多
Halloween genes are involved in the biosynthesis of the molting hormone, which plays a key role in insect ecdysis, development, metamorphosis, and reproduction. Our previous work identified five Halloween genes from L...Halloween genes are involved in the biosynthesis of the molting hormone, which plays a key role in insect ecdysis, development, metamorphosis, and reproduction. Our previous work identified five Halloween genes from Locusta migratoria, but their functions are currently unknown. In this study, the sequences of these five Halloween genes were analyzed and characterized. LmCYP307a2, LmCYP306a1, LmCYP302a1, and LmCYP315a1 were primarily expressed in the prothoracic glands, while LmCYP314a1 was universally expressed in peripheral tissues, especially in the ovaries and Malpighian tubules. All five Halloween genes were mainly expressed from the 5th to the 7th d in 5th-instar nymphs. RNA interference (RNAi) silencing of LmCYP307a2 resulted in severe molting delays and molting failure, which could be rescued by supplementary 20-hydroxyecdysone. A hematoxylin and eosin staining analysis suggested that the RNAi of LmCYP307a2 inhibited the ecdysis process by inhibiting the apolysis and degradation of the old cuticle, and by promoting the synthesis of a new cuticle. Quantitative reverse transcription polymerase chain reaction results showed that the expressions of LmE74, LmCht5, and LmCht10 were dramatically down-regulated, while that of LmChsI was substantially up-regulated, after knockdown of LmCYP307a2. The results suggest that LmCYP307a2 is related to the molt process via regulation of chitin synthesis and degradation.展开更多
20-Hydroxyecdyone (20E), an active form of ecdysteroid, is the key hormone in insect growth and development. To date five P450 enzymes involved in the last four steps of ecdysteroid biosynthesis from ketodiol to 20E n...20-Hydroxyecdyone (20E), an active form of ecdysteroid, is the key hormone in insect growth and development. To date five P450 enzymes involved in the last four steps of ecdysteroid biosynthesis from ketodiol to 20E namely Spook (Spo), Phantom (Phm), Disembodied (Dib), Shadow (Sad) and Shade (Shd) related to ecdysteroid biosynthesis, are identified and the character of last four enzymes is well studied in Drosophila melanogaster, Bombyx mori and Manduca sexta. All of these genes are called Halloween genes. In this study, we extended these works to a major pest insect in agriculture in India, the cotton leafworm Spodoptera litura (Lepidoptera: Noctuidae). We identified the sequence of five Halloween genes partially and converted into amino acid sequences and then three of them were compared with a very near African species of Spodoptera, Spodoptera littoralis. The results suggest amino acid substitution in open reading frame of phantom, shade and disembodied protein in Spodoptera litura.展开更多
It is a day on which many children dress up in unusual costumes.The day was originally called All Hallow’s Eve because it fell on Oc-tober 31, the eve of All Saint’s Day. The name was late shortenedto Halloween. Hal...It is a day on which many children dress up in unusual costumes.The day was originally called All Hallow’s Eve because it fell on Oc-tober 31, the eve of All Saint’s Day. The name was late shortenedto Halloween. Halloween derives from both pagan festival and Chri-stian worship. Many Halloween customs are based on beliefs of the past.展开更多
I received a message from Doine yesterday, saying hello to me and sharing withme some interesting things in her recent life. I am thinking of staying on campus during the winter break because some of
0n Halloween this year,the area from Huaihai Road all the way to Nanjing Road in downtown Shanghai was a sea of cosplay carnival.The costumes and celebrations took on many Chinese elements,with revelers dressing up as...0n Halloween this year,the area from Huaihai Road all the way to Nanjing Road in downtown Shanghai was a sea of cosplay carnival.The costumes and celebrations took on many Chinese elements,with revelers dressing up as current Internet influencers,classical figures in traditional Chinese culture and various walking memes.展开更多
每年的11月1日是万圣节。万圣节前夕(Halloween)孩子们穿着奇装异服,兴高采烈地玩“trick or treats?”的游戏。他们挨家挨户地去捉弄别人,所到之家都会拿出糖果、糕点来招待这些来客。不过,近些年来,情况已有所变。有些地方已禁止人们...每年的11月1日是万圣节。万圣节前夕(Halloween)孩子们穿着奇装异服,兴高采烈地玩“trick or treats?”的游戏。他们挨家挨户地去捉弄别人,所到之家都会拿出糖果、糕点来招待这些来客。不过,近些年来,情况已有所变。有些地方已禁止人们玩“恶作剧”,因为“恶作剧”已经酿成了许多不幸事件。虽然仍有不少地方坚持着这一风俗,但规模也大大地减小了。万圣节前夕人们点燃蜡烛,在桌上摆好各种糕点糖果,等着邻居的孩子敲门,可是却很少有人来。展开更多
文摘The paradigm, still around in textbooks, that ＇in insects sex is strictly genetic, thus that they do not have sex hormones＇, is mainly based on a wrong interpretation of the ＇gynandromorph argument＇. It is no longer tenable. Given the fact that vertebrates and invertebrates probably had a common, sexually reproducing ancestor, there is no reason to assume that only vertebrates need sex hormones. The major function of sex hormones is to inform the somatoplasm about developmental changes that take place in the gonads. In contrast to juvenile hormone and neuropeptides, ecdysteroids meet all criteria to act as sex hormones, which was probably their ancient role. Their much better documented role in moulting and metamorphosis was a secondary acquisition that enabled arthropods to cope with growth problems, imposed by a rigid cuticle. Female insects use 20-hydroxyecdysone （20E）, secreted by the follicle cells of the ovary, in a similar way as females of egg-laying vertebrates use estrogens. For a variety of reasons, the possibility that ecdysteroids, in particular ecdysone （E）, might also act as sex hormones in male insects, thus as the counterpart of testosterone of vertebrates, has been very much overlooked. Thanks to the recent discovery of the molecular basis of the haploid-diploid system of sex determination in the honeybee, the characterization of Halloween genes, proteomics, RNAi and so on, it now becomes possible to verify whether in insects, as with vertebrates, males are the endocrinologically default gender form.
基金This research was supported by the National Natural Science Foundation of China(General Program Grant No.31872010,32072419,32070502,31320103921)Natural Science Foundation of Shanxi Province for The Excellent Youth(Grant No.201901D211194).
文摘Halloween genes are involved in the biosynthesis of the molting hormone, which plays a key role in insect ecdysis, development, metamorphosis, and reproduction. Our previous work identified five Halloween genes from Locusta migratoria, but their functions are currently unknown. In this study, the sequences of these five Halloween genes were analyzed and characterized. LmCYP307a2, LmCYP306a1, LmCYP302a1, and LmCYP315a1 were primarily expressed in the prothoracic glands, while LmCYP314a1 was universally expressed in peripheral tissues, especially in the ovaries and Malpighian tubules. All five Halloween genes were mainly expressed from the 5th to the 7th d in 5th-instar nymphs. RNA interference (RNAi) silencing of LmCYP307a2 resulted in severe molting delays and molting failure, which could be rescued by supplementary 20-hydroxyecdysone. A hematoxylin and eosin staining analysis suggested that the RNAi of LmCYP307a2 inhibited the ecdysis process by inhibiting the apolysis and degradation of the old cuticle, and by promoting the synthesis of a new cuticle. Quantitative reverse transcription polymerase chain reaction results showed that the expressions of LmE74, LmCht5, and LmCht10 were dramatically down-regulated, while that of LmChsI was substantially up-regulated, after knockdown of LmCYP307a2. The results suggest that LmCYP307a2 is related to the molt process via regulation of chitin synthesis and degradation.
文摘20-Hydroxyecdyone (20E), an active form of ecdysteroid, is the key hormone in insect growth and development. To date five P450 enzymes involved in the last four steps of ecdysteroid biosynthesis from ketodiol to 20E namely Spook (Spo), Phantom (Phm), Disembodied (Dib), Shadow (Sad) and Shade (Shd) related to ecdysteroid biosynthesis, are identified and the character of last four enzymes is well studied in Drosophila melanogaster, Bombyx mori and Manduca sexta. All of these genes are called Halloween genes. In this study, we extended these works to a major pest insect in agriculture in India, the cotton leafworm Spodoptera litura (Lepidoptera: Noctuidae). We identified the sequence of five Halloween genes partially and converted into amino acid sequences and then three of them were compared with a very near African species of Spodoptera, Spodoptera littoralis. The results suggest amino acid substitution in open reading frame of phantom, shade and disembodied protein in Spodoptera litura.
文摘It is a day on which many children dress up in unusual costumes.The day was originally called All Hallow’s Eve because it fell on Oc-tober 31, the eve of All Saint’s Day. The name was late shortenedto Halloween. Halloween derives from both pagan festival and Chri-stian worship. Many Halloween customs are based on beliefs of the past.
文摘I received a message from Doine yesterday, saying hello to me and sharing withme some interesting things in her recent life. I am thinking of staying on campus during the winter break because some of
文摘0n Halloween this year,the area from Huaihai Road all the way to Nanjing Road in downtown Shanghai was a sea of cosplay carnival.The costumes and celebrations took on many Chinese elements,with revelers dressing up as current Internet influencers,classical figures in traditional Chinese culture and various walking memes.
文摘每年的11月1日是万圣节。万圣节前夕(Halloween)孩子们穿着奇装异服,兴高采烈地玩“trick or treats?”的游戏。他们挨家挨户地去捉弄别人,所到之家都会拿出糖果、糕点来招待这些来客。不过,近些年来,情况已有所变。有些地方已禁止人们玩“恶作剧”,因为“恶作剧”已经酿成了许多不幸事件。虽然仍有不少地方坚持着这一风俗,但规模也大大地减小了。万圣节前夕人们点燃蜡烛,在桌上摆好各种糕点糖果,等着邻居的孩子敲门,可是却很少有人来。
