PMID- 36494570
OWN - NLM
STAT- MEDLINE
DCOM- 20221229
LR  - 20230116
IS  - 2045-2322 (Electronic)
IS  - 2045-2322 (Linking)
VI  - 12
IP  - 1
DP  - 2022 Dec 9
TI  - Novel selectively amplified DNA sequences in the germline genome of the Japanese 
      hagfish, Eptatretus burgeri.
PG  - 21373
LID - 10.1038/s41598-022-26007-2 [doi]
LID - 21373
AB  - In the Japanese hagfish Eptatretus burgeri, 16 chromosomes (eliminated 
      [E]-chromosomes) have been lost in somatic cells (2n = 36), which is equivalent 
      to approx. 21% of the genomic DNA in germ cells (2n = 52). At least seven of the 
      12 eliminated repetitive DNA families isolated in eight hagfish species were 
      selectively amplified in the germline genome of this species. One of them, EEEb1 
      (eliminated element of E. burgeri 1) is exclusively localized on all 
      E-chromosomes. Herein, we identified four novel eliminated repetitive DNA 
      families (named EEEb3-6) through PCR amplification and suppressive subtractive 
      hybridization (SSH) combined with Southern-blot hybridization. EEEb3 was mosaic 
      for 5S rDNA and SINE elements. EEEb4 was GC-rich repeats and has one pair of 
      direct and inverted repeats, whereas EEEb5 and EEEb6 were AT-rich repeats with 
      one pair and two pairs of sub-repeats, respectively. Interestingly, all repeat 
      classes except EEEb3 were transcribed in the testes, although no open reading 
      frames (ORF) were identified. We conducted fluorescence in situ hybridization 
      (FISH) to examine the chromosomal localizations of EEEb3-6 and EEEb2, which was 
      previously isolated from the germline genome of E. burgeri. All sequences were 
      only found on all EEEb1-positive E-chromosomes. Copy number estimation of the 
      repeated elements by slot-blot hybridization revealed that (i) the EEEb1-6 family 
      members occupied 39.9% of the total eliminated DNA, and (ii) a small number of 
      repeats were retained in somatic cells, suggesting that there is incomplete 
      elimination of the repeated elements. These results provide new insights into the 
      mechanisms involved in the chromosome elimination and the evolution of 
      E-chromosomes.
CI  - (c) 2022. The Author(s).
FAU - Nagao, Kohei
AU  - Nagao K
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Otsuzumi, Tomoko
AU  - Otsuzumi T
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Chinone, Hitomi
AU  - Chinone H
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Sasaki, Takashi
AU  - Sasaki T
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Yoshimoto, Junko
AU  - Yoshimoto J
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Matsuda, Makiko
AU  - Matsuda M
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Kubota, Souichirou
AU  - Kubota S
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan.
FAU - Goto, Yuji
AU  - Goto Y
AD  - Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, 
      Funabashi, Chiba, 274-8510, Japan. ygoto@bio.sci.toho-u.ac.jp.
LA  - eng
PT  - Journal Article
DEP - 20221209
PL  - England
TA  - Sci Rep
JT  - Scientific reports
JID - 101563288
RN  - 0 (DNA, Ribosomal)
SB  - IM
MH  - Animals
MH  - Base Sequence
MH  - DNA, Ribosomal
MH  - Germ Cells
MH  - *Hagfishes
MH  - In Situ Hybridization, Fluorescence
MH  - Repetitive Sequences, Nucleic Acid
PMC - PMC9734144
COIS- The authors declare no competing interests.
EDAT- 2022/12/10 06:00
MHDA- 2022/12/15 06:00
PMCR- 2022/12/09
CRDT- 2022/12/09 23:42
PHST- 2022/07/16 00:00 [received]
PHST- 2022/12/07 00:00 [accepted]
PHST- 2022/12/09 23:42 [entrez]
PHST- 2022/12/10 06:00 [pubmed]
PHST- 2022/12/15 06:00 [medline]
PHST- 2022/12/09 00:00 [pmc-release]
AID - 10.1038/s41598-022-26007-2 [pii]
AID - 26007 [pii]
AID - 10.1038/s41598-022-26007-2 [doi]
PST - epublish
SO  - Sci Rep. 2022 Dec 9;12(1):21373. doi: 10.1038/s41598-022-26007-2.