Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If prog...Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If progeny derived from distant hybridization are bisexual and fertile,they can form a hybrid lineage through self-mating,with major implications for evolutionary biology,genetics,and breeding.Here,we review and summarize the published literature,and present our results on fish distant hybridization.Relevant problems involving distant hybridization between orders,families,subfamilies,genera,and species of animals are introduced and discussed,with an additional focus on fish distant hybrid lineages,genetic variation,patterns,and applications.Our review serves as a useful reference for evolutionary biology research and animal genetic breeding.展开更多
Bisexual fertile diploid androgenetic individuals(A_(0))(2n=100)were formed by androgenesis.In this way,the diploid spermatozoa from male allotetraploid hybrids(AT)(4n=200)of red crucian carp(Carassius auratus red var...Bisexual fertile diploid androgenetic individuals(A_(0))(2n=100)were formed by androgenesis.In this way,the diploid spermatozoa from male allotetraploid hybrids(AT)(4n=200)of red crucian carp(Carassius auratus red var.)(♀)×common carp(Cyprinus carpio L.)(♂)were used to fertilize the UV-treated hap-loid eggs of goldfish(Carassius auratus),and living androgenetic diploid fish were developed.The A_(0)became sexually mature at the age of 2 years,and they fertilized with each other to form their offspring(A_(1)).In this study,we observed the chromosomal number,gonadal structure and appearance of A_(1)fish.The results are as follows:(1)In A_(1),there were 85%tetraploids(A_(1)-4n),10%triploids(A_(1)-3n)and 5%diploids(A_(1)-2n),suggesting that diploid A_(0)could produce diploid gametes.It was concluded that the formation of diploid gametes generated from diploid A_(0)was probably related to the mechanism of pre-meiotic endoreduplication.(2)Among A_(1),only A_(1)-4n possessed normal ovaries and testes.The mature males of A_(1)-4n produced white semen.Under the electron microscope,the head of diploid sperm generated by A_(1)-4n was bigger than that of haploid sperm generated by red crucian carp.In the testes of the A_(1)-4n,there were many mature normal spermatozoa with a head bearing plasma mem-brane and a tail having the typical structure of"9+2"microtubules.Between the head and the tail,there were some mitochondria.The ovaries of A_(1)-4n developed well and mainly contained II,III and IV-stage oocytes.The IV-stage oocytes were surrounded by inner and outer follicular cells.The micropyle was observed on the oolemma of follicular cells.There were abundant yolks and plenty of endoplasmic reticulum in the cytoplasm of IV-stage oocytes.Because A_(1)-2n and A_(1)-3n were distant crossing diploid hybrids and triploid hybrids respectively,they possessed abnormal gonads,and no mature semen and eggs were observed.(3)Compared with allotetraploids,the A_(1)-4n fish not only had advantages such as fast growth rate and strong resistibility but also showed some new good performances such as high ratio of body width to body length,smaller heads and shorter tails.These results indicated that an-drogenesis could produce bisexual fertile tetraploids and improve the shape of allotetraploid hybrids as well,which will be of great significance in both the cell genetics research and fish breeding.展开更多
基金supported by the Major International Cooperation Projects of the National Natural Science Foundation of China(31210103918)Training Program of the Major Research Plan of the National Natural Science Foundation of China(91331105)+3 种基金the National Key Basic Research Program of China(2012CB722305)the National High Technology Research and Development Program of China(2011AA100403)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province(20134486)the Construct Program of the Key Discipline in Hunan Province and China
文摘Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If progeny derived from distant hybridization are bisexual and fertile,they can form a hybrid lineage through self-mating,with major implications for evolutionary biology,genetics,and breeding.Here,we review and summarize the published literature,and present our results on fish distant hybridization.Relevant problems involving distant hybridization between orders,families,subfamilies,genera,and species of animals are introduced and discussed,with an additional focus on fish distant hybrid lineages,genetic variation,patterns,and applications.Our review serves as a useful reference for evolutionary biology research and animal genetic breeding.
基金Supported by the National Natural Science Foundation of China(Grant Nos.30330480 and 30571444)the Doctoral Station of University of the Education Min-istry of China(Grant No.200405422001)+1 种基金the Agriculture Technological Production Foundation of the Science and Technology Ministry of China(Grant No.2005380)Important Solution Project of Hunan Province(Grant No.2006NK2008)
文摘Bisexual fertile diploid androgenetic individuals(A_(0))(2n=100)were formed by androgenesis.In this way,the diploid spermatozoa from male allotetraploid hybrids(AT)(4n=200)of red crucian carp(Carassius auratus red var.)(♀)×common carp(Cyprinus carpio L.)(♂)were used to fertilize the UV-treated hap-loid eggs of goldfish(Carassius auratus),and living androgenetic diploid fish were developed.The A_(0)became sexually mature at the age of 2 years,and they fertilized with each other to form their offspring(A_(1)).In this study,we observed the chromosomal number,gonadal structure and appearance of A_(1)fish.The results are as follows:(1)In A_(1),there were 85%tetraploids(A_(1)-4n),10%triploids(A_(1)-3n)and 5%diploids(A_(1)-2n),suggesting that diploid A_(0)could produce diploid gametes.It was concluded that the formation of diploid gametes generated from diploid A_(0)was probably related to the mechanism of pre-meiotic endoreduplication.(2)Among A_(1),only A_(1)-4n possessed normal ovaries and testes.The mature males of A_(1)-4n produced white semen.Under the electron microscope,the head of diploid sperm generated by A_(1)-4n was bigger than that of haploid sperm generated by red crucian carp.In the testes of the A_(1)-4n,there were many mature normal spermatozoa with a head bearing plasma mem-brane and a tail having the typical structure of"9+2"microtubules.Between the head and the tail,there were some mitochondria.The ovaries of A_(1)-4n developed well and mainly contained II,III and IV-stage oocytes.The IV-stage oocytes were surrounded by inner and outer follicular cells.The micropyle was observed on the oolemma of follicular cells.There were abundant yolks and plenty of endoplasmic reticulum in the cytoplasm of IV-stage oocytes.Because A_(1)-2n and A_(1)-3n were distant crossing diploid hybrids and triploid hybrids respectively,they possessed abnormal gonads,and no mature semen and eggs were observed.(3)Compared with allotetraploids,the A_(1)-4n fish not only had advantages such as fast growth rate and strong resistibility but also showed some new good performances such as high ratio of body width to body length,smaller heads and shorter tails.These results indicated that an-drogenesis could produce bisexual fertile tetraploids and improve the shape of allotetraploid hybrids as well,which will be of great significance in both the cell genetics research and fish breeding.
