hpEx2905 [myo-2p::RFP + myo-3p::daf-2]. Pick RFP+ to maintain. Maintain at 15C. Temperature sensitive dauer constitutive. [NOTE: (07-14-2015) The genotype of this strain was incorrectly reported as daf-2(e1370), but is in fact daf-2(m596).] References: Hung W, et al. EMBO J. 2013 Jun 12;32(12):1745-60. Hung W, et al. Development. 2014 Apr;141(8):1767-79.

hpIs583 [acr-2(s)p::tomm20::miniSOG::SL2::RFP]. Maintain in the covered box to avoid unnecessary exposure to ambient light. Stimulation with blue light (460 nm LED light for 30 min at 4 Hz with 2 mW/mm2), induces mitochondrial-miniSOG ablation of A- and B-class motor neurons. During neuron ablation, it is recommended to keep the lid of the plate open and use a heat disipator to keep the air cool. acr-2s(p) is a 1.8 kb fragment of the acr-2 promoter driving expression in only A- and B- class motor neurons (described in Jospin et al, 2009 PLoS Biol. Dec;7(12):e1000265). Generated in N2 background. Reference: Gao S, et al. eLife 2018 Jan 23;7:e29915. doi: 10.7554/eLife.29915.

hpIs587 [flp-14p::GCaMP6::wCherry + lin-15(+)]. CGaMP6 and wCherry expressed in RID, ALA, some head neurons, a mid-body neuron and a tail neuron. Reference: Lim et al., 2016. Elife 5. pii: e19887. doi: 10.7554/eLife.19887.

hpIs590 [ttr-39p::tomm20::miniSOG::SL2::BFP]. Maintain in the covered box to avoid unnecessary exposure to ambient light. Stimulation with blue light (460 nm LED light for 30 min at 4 Hz with 2 mW/mm2), induces mitochondrial-miniSOG ablation of D-class motor neurons. Generated in N2 background. Reference: Gao S, et al. eLife 2018 Jan 23;7:e29915. doi: 10.7554/eLife.29915.

hpIs595 [acr-2(s)p::GCaMP6s::wCherry + lin-15(+)]. Red fluorescence in motor neurons. Reference: Lu Y, et al. 2022. Current Biology (In Press).

ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. Shrinker. Reference: Lu Y, et al. 2022. Current Biology (In Press).

hpIs603 [lgc-55Bp::tomm20::miniSOG::SL2::BFP + nmr-1p::tomm20::miniSOG::SL2::BFP + acr-5p::tomm20-miniSOG-SL2::BFP + lin-15(+)]. MiniSOG neuron ablation of all premotor interneurons, B-class motor neurons (B-MN), and other neurons. Reference: Gao S, et al. eLife 2018 Jan 23;7:e29915. PMID: 29360035

hpIs625 [ttr-39p::Arch::wCherry + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. Reference: Lu Y, et al. 2022. Current Biology (In Press).

hpIs636 [rig-3p::HisCl1::SL2::mCherry]. mCherry expression in AVA soma and neurites along VNC. Non-specific mCherry expression in gut. HisCl activation leads to reduced forward and reversal activity.

zxIs6 [unc-17p::ChR2::YFP + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. Body contracts and coils dorsally upon blue light illumination on ATR plates. Reference: Lu Y, et al. 2022. Current Biology (In Press).

hpEx3370 [dpy-30p::daf-16a::unc-54 3' UTR + myo-2p::mCherry]. Pick RFP+ and keep at 15C to maintain. Can be kept at 20C, but some animals will form dauers. Transgenic strain expressing DAF-16A isoform from pan-tissue dpy-30 promoter. Transgenic animals have RFP in pharynx and will form dauers at 25C. Non-transgenic animals are dauer-defective (Daf-d). Reference: Hung WL. et al., Development (2014) 141 (8): 1767–1779.

hpEx3373 [ges-1p::GFP::daf-16a::unc-54 3' UTR + myo-2p::mCherry]. Pick RFP+ and keep at 15C to maintain. Can be kept at 20C, but some animals will form dauers. Transgenic animals have GFP in gut and RFP in pharynx and will form dauers at 25C. Non-transgenic animals will not form dauers. Reference: Hung WL. et al., Development (2014) 141 (8): 1767–1779.

hpEx3507 [ges-1p::GFP::daf-16d/f::unc-54 3' UTR + myo-2p::mCherry]. Pick RFP+ and keep at 15C to maintain. Can be kept at 20C, but some animals will form dauers. Transgenic animals have GFP in gut and RFP in pharynx and will form dauers at 25C. Non-transgenic animals will not form dauers. Reference: Hung WL. et al., Development (2014) 141 (8): 1767–1779.

hpEx3508 [ges-1p::daf-16a,d&f + myo-2p::RFP]. Pick RFP+ and keep at 15C to maintain. Can be kept at 20C, but some animals will form dauers. ges-1 promoter drives expression DAF-16A,D&F transgene in intestine. Transgenic animals have RFP in pharynx and will form dauers at 25C. Non-transgenic animals are dauer-defective (Daf-d). Reference: Hung WL. et al., Development (2014) 141 (8): 1767–1779.

hpSi38 [flp-14(+) + NeoR]. Superficially wild-type. Neomycin-resistant. hpSi38 is a single copy miniMos insertion a wild-type genomic fragment containing flp-14 and fully rescues the flp-14 mutant phenotype. Reference: Lim MA, et al. Elife. 2016 Nov 18;5:e19887. doi: 10.7554/eLife.19887. PMID: 27855782

hpSi38 [flp-14(+) + NeoR]. hpIs201[ceh-10p::GFP + lin-15(+)]. GFP expression in RID neuron. Neomycin-resistant. hpSi38 is a single copy miniMos insertion a wild-type genomic fragment containing flp-14 and fully rescues the flp-14 mutant behavioral defects and RID axon defects. Reference: Lim MA, et al. Elife. 2016 Nov 18;5:e19887. doi: 10.7554/eLife.19887. PMID: 27855782

hpIs593 [ttr-39p::Chrimson::wCherry + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. D motor neuron activation and muscle relaxation upon illumination with green light. Muscle activity measured by GCaMP3. Reference: Lu Y, et al. 2022. Current Biology (In Press).

zxIs6 [unc-17p::ChR2::YFP + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. Shrinker. Cholinergic activation. Reference: Lu Y, et al. 2022. Current Biology (In Press).

GFP tag inserted at the N-terminus (immediately in front of the ATG start codon) of the unc-2 locus specifically tagging the UNC-2B isoform. hp858 animals exhibit wildtype motor behaviors. Reference: Gao S, et al. eLife 2018 Jan 23;7:e29915. PMID: 29360035

hpIs615 [acr-2(s)p::Arch::wCherry + lin-15(+)]. hpIs365 [unc-25p::GCaMP3::wCherry + lin-15(+)]. RFP expression in motor neurons. A and B motor neurons are inhibited and body relaxes upon illumination with green light. Reference: Lu Y, et al. 2022. Current Biology (In Press).

hpIs675 [rgef-1p::GCaMP6s::3xNLS::mNeptune + lin-15(+)]. Worms express GCaMP6s and mNeptune in all neuronal nuclei. Pan-neuronal imaging strain; suitable for rapid whole-brain imaging due to brightness, good signal to noise ratio, and relative resistance to photo-bleaching. Reference: Susoy V, et al. Cell. 2021 Sep 30;184(20):5122-5137.e17. PMID: 34534446

hpIs673 [rgef-1p::Chrimson::UrSL2::wCherry + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. All neurons are marked with red fluorescence. Pan-neuronal activation and muscle contraction upon green light illumination with ATR. Reference: Lu Y, et al. 2022. Current Biology (In Press).

hpIs673 [rgef-1p::Chrimson::UrSL2::wCherry + lin-15(+)]. ljIs131 [myo-3p::GCaMP3::UrSL2::tagRFP-T]. Shrinker. All neurons are marked with red fluorescence. Pan-neuronal activation and muscle contraction upon green light illumination with ATR. Reference: Lu Y, et al. 2022. Current Biology (In Press).

648 bp deletion (confirmed). About 80% of animals show defects in vulval development (Muv or Vul).

Gonadal enlargement and aberrant gonad migration. Phenotype evident at 25C.

Heterozygotes are WT. drh-3 homozygotes are sterile. the fj52 mutation deletes a 405 bp region including the promoter, the first exon and half of the second exon. The deletion can be checked by PCR with the following primers: TTTATTGATTCCGCCGTTGCTC and TGCAGCTCCAGCCACTCTATCA. The fj52 mutation was isolated from a deletion mutant libray of the K. Nishiwaki group. Homozygous hT2[bli-4 let-? qIs48] inviable.

fjSi1 [2×FLAG::csr-1 + Cbr-unc-119(+)] II. Single-copy insertion in the MosSCI locus ttTi5605 (LG II). The 2×FLAG::csr-1 transgene was designed to express proteins with a double FLAG tag instead of the N169 of CSR-1a and N6 of CSR-1b. The linker sequence between the two FLAG tags has a NotI site. The insertion can be checked by PCR with the following primers: CACACTCGATTCTACGCCAA (at the 3'-side of csr-1) and ATCGGGAGGCGAACCTAACTG (near ttTi5605 on LG II). Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

fjSi3 [HA_2×FLAG::C04F12.1 + Cbr-unc-119(+)] II. Single-copy insertion in the MosSCI locus ttTi5605 (LG II). The HA_2×FLAG::C04F12.1 transgene was designed to express a protein with an HA tag and a double FLAG tag inserted after S21 of C04F12.1. The linker sequence between the HA tag and the double FLAG tag has a NotI site. The insertion can be checked by PCR with the following primers: GGAGCCGATTTGTTCCAGTC (at the 3'-side of C04F12.1) and ATCGGGAGGCGAACCTAACTG (near ttTi5605 on LG II). vsra-1 is also known as csr-2/C04F12.1. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Maintain at 20C or lower. The cec-4 cec-5 double mutant exhibits partial sterility and no significant defects in chromosome segregation. The chromodomain proteins CEC-4 and CEC-5 are phylogenetically similar to CEC-8. ok3124 is a 374-bp deletion located in the region of the gene corresponding to the N-terminus of CEC-4 (F32E10.2). The ok3124 deletion can be detected by PCR with the following primers: CAATTAAAATGCCAGTGCGA and TTTAGGATGCATTATGGGGC. fj58 is a 398-bp deletion located in the gene region corresponding to the N-terminus of CEC-5 (F32E10.6). The fj58 deletion can be detected by PCR with the following primers: GCAAAGAAATCATCCGGTAGTG and CTTTGTAGCAACAGGCTCCTC. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Heterozygotes are wild-type with pharyngeal GFP signal, and segregate WT GFP, arrested nT1[qIs51] aneuploids, and non-GFP csr-1(fj54) homozygotes (sterile, but some animals lay a small number of dead eggs). Homozygous nT1[qIs51] inviable. Pick WT GFP and check for correct segregation of progeny to maintain. The fj54 mutation deletes a 524 bp region including half of the second exon, the third exon, and almost all of the fourth exon, causing a frame shift to stop the translation of both PAZ and Piwi domains. The deletion can be checked by PCR with the following primers: AAGAAATACCAATGCGGAGGCA and TTCACGGCTCTTTGCAGTTTCA.

Maintain at 20C or lower. Him. cec-4 cec-5 him-8 triple mutants exhibit partial sterility. The intensity of histone H3K9me2 on meiotic chromosomes is reduced. ok3124 deletion can be detceted by PCR with the following primers: CAATTAAAATGCCAGTGCGA and TTTAGGATGCATTATGGGGC. fj61 is a 444-bp deletion located in the region of the gene corresponding to the N-terminus of CEC-5 (F32E10.6). The fj61 deletion can be detected by PCR with the following primers: GCAAAGAAATCATCCGGTAGTG and CTTTGTAGCAACAGGCTCCTC. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

No apparent phenotype. The chromodomain protein CEC-8 is phylogenetically similar to CEC-5 and CEC-4. fj63 is a 14-bp deletion located in the region of the gene corresponding to the N-terminus of CEC-8 (Y55B1BR.3). The fj63 deletion can be detected by PCR with the following primers: GCTGTATAATACTCACTATGTC and TCCAGCTCTGTAACCTTGAA. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Maintain at 20C or lower. cec-8; cec-4 cec-5 triple mutants exhibit partial sterility and no significant defects in chromosome segregation. The chromodomain proteins CEC-5, CEC-4, and CEC-8 are phylogenetically similar to each other. The deletions can be detected by PCR with the following primers: cec-8(fj63): GCTGTATAATACTCACTATGTC and TCCAGCTCTGTAACCTTGAA; cec-4(ok3124): CAATTAAAATGCCAGTGCGA and TTTAGGATGCATTATGGGGC; cec-5(fj58): GCAAAGAAATCATCCGGTAGTG and CTTTGTAGCAACAGGCTCCTC. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Maintain at 20C or lower. Him. The cec-8; cec-4 cec-5 him-8 quadruple mutant exhibits partial sterility. The intensity of histone H3K9me2 on meiotic chromosomes is reduced. The deletions can be detected by PCR with the following primers: cec-8(fj63): GCTGTATAATACTCACTATGTC and TCCAGCTCTGTAACCTTGAA; cec-4(ok3124): CAATTAAAATGCCAGTGCGA and TTTAGGATGCATTATGGGGC; cec-5(fj58): GCAAAGAAATCATCCGGTAGTG and CTTTGTAGCAACAGGCTCCTC. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Heterozygotes are WT and GFP+ and segregate WT GFP+ heterozygotes, non-GFP ego-1 homozygotes (sterile with inaccurate homologous pairing of meiotic chromosomes), very rare GFP+ homozygous hT2, and dead eggs. Maintain by picking wild-type GFP+. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Heterozygotes are wild-type with pharyngeal GFP signal, and segregate WT GFP, arrested nT1[qIs51] aneuploids, and non-GFP csr-1(fj67) homozygotes (sterile, but some animals lay a small number of dead eggs). Homozygous nT1[qIs51] inviable. Pick WT GFP and check for correct segregation of progeny to maintain. Intracellular localization of CSR-1 is abnormal in the csr-1(fj67) homozygotes. fj67 is a 60-bp in-frame deletion of the first lysine-rich region (KQKDNFILLDILLKQWAAKK) in CSR-1. The first lysine-rich region in the WT has a FokI site. The deletion can be checked by PCR with the following primers: CACCTGTGATTTTTCGGGGAAC and TGGATTCCTTTTGCTGCAACAG, followed by digestion with FokI. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Heterozygotes are wild-type with pharyngeal GFP signal, and segregate WT GFP, arrested nT1[qIs51] aneuploids, and non-GFP csr-1(fj70) homozygotes (sterile, but some animals lay a small number of dead eggs). Homozygous nT1[qIs51] inviable. Pick WT GFP and check for correct segregation of progeny to maintain. fj70 is a D769L mutation that renders CSR-1 (an Argonaute protein) catalytically defective and generates a new SphI site. The fj70 mutation can be checked by PCR with the following primers: TACACGTGGATGATGAGAAG and TCGTCCGAAACTTCCTCATC, followed by digestion with SphI. Homozygous nT1[qIs51] inviable. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Four amino-acid residues (G24–V27) near the N-terminus of EGO-1 were replaced with a PA-tag sequence (GVAMPGAEDDVV derived from human podoplanin) in the endogenous ego-1 gene. The PA-tag insertion can be checked by PCR with the following primers: TTCAAAATGCCGCTGCCTTC and GTCCTCTTCGCATCTTTATCAG, followed by digestion with Sau96I. The wild-type ego-1 gene contains a Sau96I site within its PCR region, while the PA-tagged ego-1 does not. This strain was used for immunofluorescence analysis of EGO-1. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

fjSi19 [rpl-21p::2×HA::C04F12.1 + Cbr-unc-119(+)] II. Single-copy insertion in the MosSCI locus ttTi5605 (LG II). The 2×HA::C04F12.1 transgene was designed to express a protein with a double HA tag at its N-terminus, using a strong ubiquitous promoter (rpl-21p). The linker sequence between the two HA tags has a NotI site. The insertion can be checked by PCR with the following primers: GGAGCCGATTTGTTCCAGTC (at the 3'-side of C04F12.1) and ATCGGGAGGCGAACCTAACTG (near ttTi5605 on LG II). vsra-1 is also known as csr-2/C04F12.1. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Heterozygotes are wild-type with pharyngeal GFP signal, and segregate WT GFP, arrested nT1[qIs51] aneuploids, and non-GFP csr-1(fj126) homozygotes (sterile, but some animals lay a small number of dead eggs). Homozygous nT1[qIs51] inviable. Pick WT GFP and check for correct segregation of progeny to maintain. fj126 was generated by the insertion of a synthetic nuclear export signal (NES). Instead of six amino-acid residues (R8–I13) near the N-terminus of CSR-1b, an NES sequence (LNELALKLAGLDI) from the cAMP-dependent protein kinase inhibitor alpha in mammals was inserted into the endogenous csr-1 gene. The DNA sequence encoding the NES has a HindIII site. The fj126 mutation can be checked by PCR with the following primers: AAGAAATACCAATGCGGAGGCA and CCGCTGAGGAACGAGATGG, followed by digestion with HindIII. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

CeRep55 quadruple deletion: fjDf1 (also known as fj115); fjDf2 (aka fj85); fjDf3 (aka fj123); fjDf4 (aka fj120) X. This strain lacks four major clusters of CeRep55 repeats on the X chromosome. The condensation of unpaired X chromosomes in male testes is insufficient. CeRep55 is a class of minisatellite sequences consisting of a 27-nt tandem repeat that is present on all chromosomes. Some CeRep55 clusters express long non-coding RNAs and small RNAs. Each of the four deletion sites was designed to acquire a sequence tag (TGTACAGGAAACAGCTATGACC; similar to M13 reverse) instead of the CeRep55 tandem repeats. The deletions of CeRep55 clusters can be checked by PCR with the following primers: fjDf1 in Y73B3A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA; fjDf2 in Y75D11A, CAAGTGCCAAACTAGACTGCTC and TTCAAAACGCTACGCGATACCAG; fjDf3 in Y81B9A, AAATGCCCCTATCTCACAGTGG and GACTGCTAGAATCTGACTCGTC; fjDf4 in Y49A10A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA. The PCR check can also be performed with the M13 reverse primer and the right-side primer. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Sterile csr-1 allele balanced over tmC5 labelled with Venus. Heterozygotes are wild-type with somewhat dimmer Venus signal and segregate WT Venus(+) heterozygotes, Mec Unc Venus(+) tmC5 homozygotes, and non-Venus csr-1(fj54) homozygotes (sterile, but some animals lay a small number of dead eggs). Pick wild-type Venus(+) and check for proper segregation of progeny to maintain. Homologous pairing and unpaired silencing of meiotic chromosomes are inaccurate in this csr-1 null-mutant homozygotes. The fj54 deletion causes a frame-shift to stop the translation of both PAZ and Piwi domains. The deletion can be checked by PCR with the following primers: AAGAAATACCAATGCGGAGGCA and TTCACGGCTCTTTGCAGTTTCA. The inversion-based balancer in ZT60 is more amenable to producing csr-1(fj54) homozygous males than a translocation-based balancer (ZT3). Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Sterile csr-1 allele balanced over tmC5 labelled with Venus. Heterozygotes are wild-type with somewhat dimmer Venus signal and segregate WT Venus(+) heterozygotes, Mec Unc Venus(+) tmC5 homozygotes, and non-Venus csr-1(fj54) homozygotes (sterile, but some animals lay a small number of dead eggs). Pick wild-type Venus(+) and check for proper segregation of progeny to maintain. Homologous pairing and unpaired silencing of meiotic chromosomes are inaccurate in homozygous tm1637; fj54 double mutants. The vsra-1 mutation enhances the defects caused by the csr-1 mutation. The fj54 deletion causes a frame-shift to stop the translation of both PAZ and Piwi domains. tm1637 can be detected by PCR with the following primers: AAGCAGTTCTTCAAGACTGGTC and TTGTCCACTCGCACTTTGTG. The fj54 deletion can be checked by PCR with the following primers: AAGAAATACCAATGCGGAGGCA and TTCACGGCTCTTTGCAGTTTCA. vsra-1 is also known as csr-2/C04F12.1. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

Maintain at 20C or lower. The met-2 set-25 double mutant exhibits partial sterility and no significant defects in chromosome segregation. MET-2 and SET-25 are the methyltransferases responsible for histone H3K9me2 and H3K9me3. The deletion mutations can be checked by PCR with the following primers: met-2(ok2307), GGTTGATGCGGAGAAGACTG and AATGGATTCGGTGCTTCGTG; set-25(n5021), GAGCCCGTGCCACAGAGTAG and CCTAGAGCGATGTCCTTGATGG. This strain was used as a negative control in the immunodetection of H3K9me2.

RNAi deficient (Rde). Him. Partially-inaccurate paring of meiotic chromosomes. fj150 is a mutation changing WK to FS and generating a new FspI site in the second K-rich region between the PAZ and Piwi domains. The fj150 mutation can be detected by PCR with the following primers: TCGGATGTTGACTACAACGC and GAAGGTAGAAACTTCATTCCAGCAC, followed by digestion with FspI. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

fj150 is a mutation changing WK to FS and generating a new FspI site in the second K-rich region between the PAZ and Piwi domains. fj150 is enhanced by the CeRep55 quadruple deletion. The fj150 mutation can be detected by PCR with the following primers: TCGGATGTTGACTACAACGC and GAAGGTAGAAACTTCATTCCAGCAC, followed by digestion with FspI. This strain lacks four major clusters of CeRep55 repeats on the X chromosome. The condensation of unpaired X chromosomes in male testes is insufficient. CeRep55 is a class of minisatellite sequences consisting of a 27-nt tandem repeat that is present on all chromosomes. Some CeRep55 clusters express long non-coding RNAs and small RNAs. Each of the four deletion sites was designed to acquire a sequence tag (TGTACAGGAAACAGCTATGACC; similar to M13 reverse) instead of the CeRep55 tandem repeats. The deletions of CeRep55 clusters can be checked by PCR with the following primers: fjDf1 in Y73B3A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA; fjDf2 in Y75D11A, CAAGTGCCAAACTAGACTGCTC and TTCAAAACGCTACGCGATACCAG; fjDf3 in Y81B9A, AAATGCCCCTATCTCACAGTGG and GACTGCTAGAATCTGACTCGTC; fjDf4 in Y49A10A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA. The PCR check can also be performed with the M13 reverse primer and the right-side primer. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

The CeRep55_X quadruple-deletion mutant does not exhibit a clear Him phenotype, but the Him phenotype of the him-1(e879) mutant is enhanced by the CeRep55_X quadruple deletions. CeRep55 quadruple deletion: fjDf1 (also known as fj115); fjDf2 (aka fj85); fjDf3 (aka fj123); fjDf4 (aka fj120) X. This strain lacks four major clusters of CeRep55 repeats on the X chromosome. The condensation of unpaired X chromosomes in male testes is insufficient. CeRep55 is a class of minisatellite sequences consisting of a 27-nt tandem repeat that is present on all chromosomes. Some CeRep55 clusters express long non-coding RNAs and small RNAs. Each of the four deletion sites was designed to acquire a sequence tag (TGTACAGGAAACAGCTATGACC; similar to M13 reverse) instead of the CeRep55 tandem repeats. The deletions of CeRep55 clusters can be checked by PCR with the following primers: fjDf1 in Y73B3A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA; fjDf2 in Y75D11A, CAAGTGCCAAACTAGACTGCTC and TTCAAAACGCTACGCGATACCAG; fjDf3 in Y81B9A, AAATGCCCCTATCTCACAGTGG and GACTGCTAGAATCTGACTCGTC; fjDf4 in Y49A10A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA. The PCR check can also be performed with the M13 reverse primer and the right-side primer. The e879 mutation can be checked by PCR with the following primers: AAATCAGGAGTGGGCATCAG and GGGAAGATTCCGATGAGTGA, followed by digestion with MvaI. The wild-type him-1 gene contains an MvaI site within its PCR region, while the e879 allele does not. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

RNAi deficient (Rde). High incidence of males (Him). fj162 at the second K-rich region is an in-frame duplication (comprising of a small duplication and a tiny inverted duplication) generating 61 extra amino acids. The fj162 mutation can be checked by PCR with the following primers: TCGGATGTTGACTACAACGC and GAAGGTAGAAACTTCATTCCAGCAC.

fj162 at the second K-rich region is an in-frame duplication (comprising of a small duplication and a tiny inverted duplication) generating 61 extra amino acids. The CeRep55_X quadruple-deletion mutant does not exhibit a clear Him phenotype, but the Him phenotype of the csr-1(fj162) mutant is enhanced by the CeRep55_X quadruple deletions. The fj162 mutation can be checked by PCR with the following primers: TCGGATGTTGACTACAACGC and GAAGGTAGAAACTTCATTCCAGCAC. This strain lacks four major clusters of CeRep55 repeats on the X chromosome. The condensation of unpaired X chromosomes in male testes is insufficient. CeRep55 is a class of minisatellite sequences consisting of a 27-nt tandem repeat that is present on all chromosomes. Some CeRep55 clusters express long non-coding RNAs and small RNAs. Each of the four deletion sites was designed to acquire a sequence tag (TGTACAGGAAACAGCTATGACC; similar to M13 reverse) instead of the CeRep55 tandem repeats. The deletions of CeRep55 clusters can be checked by PCR with the following primers: fjDf1 in Y73B3A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA; fjDf2 in Y75D11A, CAAGTGCCAAACTAGACTGCTC and TTCAAAACGCTACGCGATACCAG; fjDf3 in Y81B9A, AAATGCCCCTATCTCACAGTGG and GACTGCTAGAATCTGACTCGTC; fjDf4 in Y49A10A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA. The PCR check can also be performed with the M13 reverse primer and the right-side primer. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.

This strain carries a dpy-5 mutation to facilitate genome modification in CeRep55 quadruple deletion background: fjDf1 (also known as fj115); fjDf2 (aka fj85); fjDf3 (aka fj123); fjDf4 (aka fj120) X. This strain lacks four major clusters of CeRep55 repeats on the X chromosome. The condensation of unpaired X chromosomes in male testes is insufficient. CeRep55 is a class of minisatellite sequences consisting of a 27-nt tandem repeat that is present on all chromosomes. Some CeRep55 clusters express long non-coding RNAs and small RNAs. Each of the four deletion sites was designed to acquire a sequence tag (TGTACAGGAAACAGCTATGACC; similar to M13 reverse) instead of the CeRep55 tandem repeats. The deletions of CeRep55 clusters can be checked by PCR with the following primers: fjDf1 in Y73B3A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA; fjDf2 in Y75D11A, CAAGTGCCAAACTAGACTGCTC and TTCAAAACGCTACGCGATACCAG; fjDf3 in Y81B9A, AAATGCCCCTATCTCACAGTGG and GACTGCTAGAATCTGACTCGTC; fjDf4 in Y49A10A, CAACCTGACTCTCGCCAAGAC and GGAGAAGTAGGCGTGTCAGTTA. The PCR check can also be performed with the M13 reverse primer and the right-side primer. Reference: Tabara H, et al. (2023) A small RNA system ensures accurate homologous pairing and unpaired silencing of meiotic chromosomes. EMBO J, e105002.