Primer set for detection of Zaire ebola virus, assay kit, and amplification method

1. A nucleic acid primer set for LAMP amplification that specifically amplifies a Zaire Ebola virus,

wherein a template sequence to be amplified by the primer set includes an F3c sequence, an F2c sequence, an F1c sequence, a B1 sequence, a B2 sequence, and a B3 sequence from 3′ side toward the 5′ side in this order,

the primer set includes an FIP primer, an F3 primer, a BIP primer, and a B3 primer, the FIP primer includes a F1c sequence and a F2 sequence from the 5′ side toward the 3′ side in this order, the F3 primer includes a F3 sequence, the BIP primer includes a B1c sequence and a B2 sequence from the 5′ side toward the 3′ side in this order, the B3 primer includes a B3 sequence,

wherein F1 and F1c sequences are complementary to each other, F2 and F2c sequences are complementary to each other, F3 and F3c sequences are complementary to each other, B1 and the B1c sequences are complementary to each other, B2 and B2c sequences are complementary to each other, and B3 and B3c sequences are complementary to each other, and

wherein the F1 sequence includes at least 13 consecutive bases included in SEQ ID NO: 31 or 64 or complementary sequences of the bases,

the F2 sequence includes at least 13 consecutive bases included in SEQ ID NO: 62 or 63 or complementary sequences of the bases,

the F3 sequence includes at least 13 consecutive bases included in SEQ ID NO: 29, 36, 38, 55, 56, 57, 58, 59, 60 or 61 or complementary sequences of the bases,

the B1c sequence includes at least 13 consecutive bases included in SEQ ID NO: 68, 69, 70, 71, 72, 73, 74 or 75 or complementary sequences of the bases,

the B2c sequence includes at least 13 consecutive bases included in SEQ ID NO: 65 or 66 or complementary sequences of the bases, and

the B3c sequence includes at least 13 consecutive bases included in SEQ ID NO: 34, 67, 82 or 83 or complementary sequences of the bases.

2. The primer set of claim 1 ,

wherein the F3 primer is at least 13 consecutive bases so as to include consecutive bases from any of the bases at positions 1-5 from the 5′ end which are included in SEQ ID NO: 29, 55, 60 or 61, or complementary sequences of the bases,

the FIP primer includes a sequence represented by SEQ ID NO: 4, 44 or 45 or complementary sequences of the sequences and includes and includes a sequence represented by SEQ ID NO: 3 or 42 or complementary sequences of the sequences,

the B1c sequence in the BIP primer is at least 13 consecutive bases so as to include any of the bases at positions 1-5 from the 5′ end which are included in SEQ ID NO: 75 or complementary sequences of the bases, or at least 13 consecutive bases so as to include any of the bases at positions 1-6 from the 3′ end or complementary sequences of the bases, the B2c sequence is at least 13 consecutive bases so as to include any of the bases at positions 1-7 from the 5′ end which are included in SEQ ID NO: 65 or 66 or complementary sequences of the bases,

the B3 primer is at least 13 consecutive bases so as to include any of the bases at positions 1-5 from the 5′ end which is included in SEQ ID NO: 82 or complementary sequences of the bases, or at least 13 consecutive bases so as to include any of the bases at positions 1-7 from the 3′ end which is included in SEQ ID NO: 34 or complementary sequences of the bases, and

the LFc primer includes a sequence represented by SEQ ID NO: 11.

3. The primer set of claim 1 ,

wherein the F3 primer includes a sequence represented by any of SEQ ID NO: 2, 17, 20, 22, and 39 or a complementary sequence of the sequence,

the FIP primer includes a sequence represented by any of SEQ ID NO: 12, 18, and 21 or a complementary sequence of the sequence,

the BIP primer includes a sequence represented by any of SEQ ID NO: 13, 23, 24, 25, 26, and 27 or a complementary sequence of the sequence, and

the B3 primer includes a sequence represented by either SEQ ID NO: 10 or 19 or a complementary sequence of the sequence.

4. The primer set of claim 1 ,

wherein the F3 primer includes at least 13 consecutive bases which are included in a sequence represented by any of SEQ ID NOS: 2, 17, 20, 22, and 39 or a complementary sequence of the sequence,

the FIP primer includes at least 13 consecutive bases which are included in a sequence represented by any of SEQ ID NOS: 12, 18, and 21 or a complementary sequence of the sequence,

the BIP primer includes at least 13 consecutive bases which are included in a sequence represented by any of SEQ ID NOS: 13, 23, 24, 25, 26, and 27 or a complementary sequence of the sequence, and

the B3 primer includes at least 13 consecutive bases which are included in a sequence represented by either SEQ ID NO: 10 or 19 or a complementary sequence of the sequence.

5. The primer set of claim 1 ,

wherein each combination of recognition sequences for the F3, FIP, BIP, and B3 primers included in the primer set is selected from the group consisting of the followings (1) to (19):

(1) a combination of SEQ ID NOS: 17, 18, 13, and 19;

(2) a combination of SEQ ID NOS: 22, 21, 15, and 10;

(3) a combination of SEQ ID NOS: 20, 21, 23, and 10;

(4) a combination of SEQ ID NOS: 22, 21, 24, and 10;

(5) a combination of SEQ ID NOS: 22, 21, 25, and 10;

(6) a combination of SEQ ID NOS: 22, 21, 26, and 10;

(7) a combination of SEQ ID NOS: 22, 21, 27, and 10;

(8) a combination of SEQ ID NOS: 20, 12, 23, and 10;

(9) a combination of SEQ ID NOS: 20, 12, 24, and 10;

(10) a combination of SEQ ID NOS: 20, 12, 25, and 10;

(11) a combination of SEQ ID NOS: 20, 12, 26, and 10;

(12) a combination of SEQ ID NOS: 20, 12, 27, and 9;

(13) a combination of SEQ ID NOS: 20, 12, 13, and 9;

(14) a combination of SEQ ID NOS: 20, 12, 13, and 19;

(15) a combination of SEQ ID NOS: 22, 12, 13, and 10;

(16) a combination of SEQ ID NOS: 22, 12, 13, and 19;

(17) a combination of SEQ ID NOS: 39, 12, 13, and 10;

(18) a combination of SEQ ID NOS: 2, 12, 13, and 10; and

(19) a combination of complementary sequences of four sequences included in the combinations (1) to (18).

6. The primer set of claim 1 , wherein the Zaire Ebola virus is Guinea 14 strain.

7. The primer set of claim 1 , wherein the Zaire Ebola virus is Guinea 14 strain, Zaire 76 strain or Zaire 95 strain.

8. The primer set of claim 1 ,

wherein the FIP primer further includes a linker between the F1c sequence and the F2 sequence and/or the BIP primer includes a linker between the B1 sequence and the B2c sequence.

9. The primer set of claim 8 , wherein the linker is formed of an arbitrary base sequence having a base length of 1 to 50.

10. The primer set of claim 1 , further comprising an LFc primer that includes a sequence represented by SEQ ID NO: 11 or a complementary sequence of the sequence.

11. An assay kit for detecting Zaire Ebola virus comprising:

a primer set of claim 1 ; and

a container that accommodates the primer set.

12. The assay kit of claim 11 , wherein the Zaire Ebola virus is Guinea 14 strain.

13. The assay kit of claim 11 , wherein the Zaire Ebola virus is Zaire 76 strain, Zaire 95 strain or Guinea 14 strain.

14. A nucleic acid structure comprising:

a first stern-loop structure which includes an F1 sequence, an F2c sequence, and an F1c sequence from the 3′ side toward the 5′ side in this order and in which the F1 sequence is bound to the F1c sequence to form a double-strand;

a second stem-loop structure which includes an B1 sequence, an B2 sequence, and an B1c sequence from the 3′ side toward the 5′ side in this order and in which the B1 sequence is bound to the B1c sequence to form a double-strand;

a third stem-loop structure which includes an F1c sequence, an F2 sequence, and an F1 sequence from the 5′ side toward the 3′ side in this order and in which the F1c sequence is bound to the F1 sequence to form a double-strand;

a fourth stem-loop structure which includes a B1c sequence, a B2c sequence, and a B1 sequence from the 5′ side toward the 3′ side in this order and in which the B1c sequence is bound to the B1 sequence to form a double-strand;

a first dumbbell structure which includes an F1 sequence, an F2c sequence, an F1c sequence, a B1 sequence, a B2 sequence, and a B1c sequence from the 3′ side toward the 5′ side in this order and in which the F1 sequence is bound to the F1c sequence to form a double-strand, the B1 sequence is bound to the B1c sequence to form a double-strand; and/or

a second dumbbell structure which includes an F1c sequence, an F2 sequence, an F1 sequence, a B1c sequence, a B2c sequence, and a B1 sequence from the 3′ side toward the 5′ side in this order and in which the F1c sequence is bound to the F1 sequence to form a double-strand, the B1c sequence is bound to the B1 sequence to form a double-strand;

wherein F1 and F1c sequences are complementary to each other, F2 and F2c sequences are complementary to each other, F3 and F3c sequences are complementary to each other, B1 and B1c sequences are complementary to each other, B2 and B2c sequences are complementary to each other, and B3 and B3c sequences are complementary to each other, and

wherein the F1 sequence includes at least 13 consecutive bases included in SEQ ID NO: 31 or 64 or complementary sequences of the bases,

the F2 sequence includes at least 13 consecutive bases included in SEQ ID NO: 62 or 63 or complementary sequences of the bases,

the F3 sequence includes at least 13 consecutive bases included in SEQ ID NO: 29, 36, 38, 55, 56, 57, 58, 59, 60 or 61 or complementary sequences of the bases,

the B1c sequence includes at least 13 consecutive bases included in SEQ ID NO: 68, 69, 70, 71, 72, 73, 74 or 75 or complementary sequences of the bases,

the B2c sequence includes at least 13 consecutive bases included in SEQ ID NO: 65 or 66 or complementary sequences of the bases, and

the B3c sequence includes at least 13 consecutive bases included in SEQ ID NO: 34, 67, 82, or 83 or complementary sequences of the bases.

15. The nucleic acid structure of claim 14 , wherein the nucleic acid structure is derived from Guinea 14 strain of Zaire Ebola virus as a template.

16. The nucleic acid structure of claim 15 , wherein the Zaire Ebola virus is Guinea 14 strain, Zaire 76 strain or Zaire 95 strain.

17. A method of detecting Zaire Ebola virus, comprising:

amplifying a nucleic acid included in a specimen using the primer set of claim 1 ; and

determining whether the Zaire Ebola virus is included in the specimen according to turbidity or fluorescence.

18. The method of claim 17 , wherein the Zaire Ebola virus is Guinea 14 strain.

19. The method of claim 17 , wherein the Zaire Ebola virus is Guinea 14 strain, Zaire 76 strain or Zaire 95 strain.