Detection of B chromosomes in interphase hemolymph nuclei from living specimens of the grasshopper Eyprepocnemis plorans

The two most important evolutionary properties of B chromosomes are their transmission rate (which suggests their selfishness when significantly higher than 0.5) and their net effects on carrier fitness (usually negative for parasitic Bs). The study of transmission rate unavoidably requires the analysis of many controlled crosses in order to accurately measure population average transmission rate. Therefore, getting a marker closely associated to B presence is of crucial importance to alleviate the load of performing many useless crosses between lacking B individuals. After investigating several cytogenetic techniques on several tissues that may be sampled without drastically damaging live specimens of the grasshopper Eyprepocnemis plorans, we report here the excellent results provided by the CMA3 fluorescence and C-banding techniques applied to hemocyte nuclei. These cells may be easily obtained from both males and females and provide information on B presence even during the interphase stage. The two cytogenetic techniques take advantage of the heterochromatic nature of the B chromosomes, so that Bs made predominantly of ribosomal DNA are revealed by CMA3 as bright bodies in the interphase hemocytes, and Bs mostly made of satellite DNA are visualized by C-banding as intensely stained bodies in these cells.

[1]  J. S. Heslop-Harrison,et al.  Possible origin of a B chromosome deduced from its DNA composition using double FISH technique , 1994, Chromosome Research.

[2]  J. Camacho.  CHAPTER 4 – B Chromosomes , 2005 .

[3]  A. Nappi,et al.  Genetics of anti-parasite resistance in invertebrates. , 2005, Developmental and comparative immunology.

[4]  J. Camacho.  B Chromosomes in the Eukaryote Genome , 2004 .

[5]  F. Perfectti,et al.  Rapid suppression of drive for a parasitic B chromosome , 2004, Cytogenetic and Genome Research.

[6]  L. Cerenius,et al.  The prophenoloxidase‐activating system in invertebrates , 2004, Immunological reviews.

[7]  K. Anderson,et al.  Drosophila: the genetics of innate immune recognition and response. , 2004, Annual review of immunology.

[8]  W. Peacock,et al.  Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives , 1982, Chromosoma.

[9]  W. Peacock,et al.  Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives , 1981, Chromosoma.

[10]  D. Schweizer.  Reverse fluorescent chromosome banding with chromomycin and DAPI , 1976, Chromosoma.

[11]  M. White,et al.  Cytogenetics of the parthenogenetic grasshopper Warramaba virgo and its bisexual relatives , 2004, Chromosoma.

[12]  P. G. Martin,et al.  Parallel mosaicism of supernumerary chromosomes and sex chromosomes in Echymipera kalabu (Marsupialia) , 2004, Chromosoma.

[13]  M. Bakkali,et al.  Common origin of B chromosome variants in the grasshopper Eyprepocnemis plorans , 1999, Heredity.

[14]  J. Camacho,et al.  POLYMORPHISM REGENERATION FOR A NEUTRALIZED SELFISH B CHROMOSOME , 1998, Evolution; international journal of organic evolution.

[15]  M. Shaw,et al.  Population Dynamics of A Selfish B Chromosome Neutralized by the Standard Genome in the Grasshopper Eyprepocnemis Plorans , 1997, The American Naturalist.

[16]  G. Hewitt,et al.  Cloning and sequence analysis of an extremely homogeneous tandemly repeated DNA in the grasshopper Eyprepocnemis plorans , 1995, Heredity.

[17]  S. Kubota,et al.  Germ line-restricted supernumerary (B) chromosomes in Eptatretus okinoseanus. , 1992, Cytogenetics and Cell Genetics.

[18]  J. Navas-Castillo,et al.  G banding in two species of grasshopper and its relationship to C, N, and fluorescence banding techniques , 1991 .

[19]  F. Lallier,et al.  Hemolymph oxygen transport during environmental hypoxia in the shore crab, Carcinus maenas. , 1989, Respiration physiology.

[20]  J. Duman,et al.  The role of hemolymph proteins in the cold tolerance of insects. , 1983, Annual review of physiology.

[21]  K. Larsen.  [A & B chromosomes. I]. , 1959, Nordisk medicin.