| 主权项 |
1. A nitrogen-sensitive expression system comprising:
a nucleic acid sequence comprising an upstream truncated or downstream truncated variant of SEQ ID NO: 234 or a sequence having at least 95% sequence identity to said truncated sequence; wherein the upstream truncated or downstream truncated variant of SEQ ID NO: 234 or the sequence having at least 95% sequence identity thereto comprises (i) a transcription factor region comprising an NtcA binding site, (ii) a core promoter region, and (iii) nitrogen-sensitive promoter activity; wherein,
the upstream truncated variant of SEQ ID NO: 234 does not contain
(a) nucleotide positions 1 to 78 of SEQ ID NO: 234,(b) nucleotide positions 1 to 128 of SEQ ID NO: 234,(c) nucleotide positions 1 to 138 of SEQ ID NO: 234,(d) nucleotide positions 1 to 148 of SEQ ID NO: 234,(e) nucleotide positions 1 to 158 of SEQ ID NO: 234,(f) nucleotide positions 1 to 166 of SEQ ID NO: 234,(g) nucleotide positions 1 to 168 of SEQ ID NO: 234,(h) nucleotide positions 1 to 178 of SEQ ID NO: 234,(i) nucleotide positions 1 to 188 of SEQ ID NO: 234,(j) nucleotide positions 1 to 198 of SEQ ID NO: 234,(k) nucleotide positions 1 to 208 of SEQ ID NO: 234,(l) nucleotide positions 1 to 218 of SEQ ID NO: 234,(m) nucleotide positions 1 to 228 of SEQ ID NO: 234, or(n) nucleotide positions 1 to 238 of SEQ ID NO: 234; orthe downstream truncated variant of SEQ ID NO: 234 does not contain
(a) nucleotide positions 347 to 836 of SEQ ID NO: 234,(b) nucleotide positions 353 to 836 of SEQ ID NO: 234,(c) nucleotide positions 357 to 836 of SEQ ID NO: 234,(d) nucleotide positions 367 to 836 of SEQ ID NO: 234,(e) nucleotide positions 377 to 836 of SEQ ID NO: 234,(f) nucleotide positions 387 to 836 of SEQ ID NO: 234,(g) nucleotide positions 397 to 836 of SEQ ID NO: 234,(h) nucleotide positions 407 to 836 of SEQ ID NO: 234,(i) nucleotide positions 417 to 836 of SEQ ID NO: 234,(j) nucleotide positions 427 to 836 of SEQ ID NO: 234,(k) nucleotide positions 477 to 836 of SEQ ID NO: 234,(l) nucleotide positions 527 to 836 of SEQ ID NO: 234,(m) nucleotide positions 577 to 836 of SEQ ID NO: 234,(n) nucleotide positions 627 to 836 of SEQ ID NO: 234,(o) nucleotide positions 677 to 836 of SEQ ID NO: 234,(p) nucleotide positions 727 to 836 of SEQ ID NO: 234,(q) nucleotide positions 777 to 836 of SEQ ID NO: 234,(r) nucleotide positions 807 to 836 of SEQ ID NO: 234, or(s) nucleotide positions 817 to 836 of SEQ ID NO: 234, wherein,
the core promoter region comprises or is operably linked to the transcription factor region; andthe nitrogen-sensitive promoter activity comprises promoter activity when urea or ammonia is the predominant nitrogen source and promoter repression when nitrate is a predominant nitrogen source;the nitrogen-sensitive expression system further comprises a transcribable nucleic acid molecule and a 3′ transcription termination nucleic acid molecule;the core promoter region is operably linked to the transcribable nucleic acid molecule;the transcribable nucleic acid molecule is operably linked to the 3′ transcription termination nucleic acid molecule;expression of the transcribable nucleic acid molecule is repressed when nitrate is a predominant nitrogen source and the transcribable nucleic acid molecule is expressed when urea or ammonia is the predominant nitrogen source; andthe transcribable nucleic acid molecule encodes a polypeptide having sucrose phosphate synthase activity; sucrose phosphate phosphatase activity, sucrose phosphate synthase and sucrose phosphate phosphatase activity; trehalose phosphate synthase activity; trehalose phosphate phosphatase activity, gluocosylglycerol phosphate synthase activity; gluocosylglycerol phosphate phosphatase activity;mannosylfructose phosphate synthase activity; or mannosylfructose phosphate phosphatase activity. |
