Gene: [01p/SRM] spermidine synthase (aminopropyltransferase);


COM

By using Southern blot analysis of panels of human/rodent somatic cell hybrids and in situ hybridization, Winqvist-1991 mapped SRM-like DNA sequences on two different chromosome regions - 1p36-p22 and 3p14-q21. Comparing the intensity of the hybridization signals, the authors suggested that 'the former chromosomal site harbors the functional gene, SPS1, and the latter site a pseudogene, SPS2' (see GEM:03^/SRML2)."

FUN

[1] Systematic name: S-adenosylmethioninamine:putrescine 3-aminopropyltransferase.
[2] The reaction catalyzed: S-adenosylmethioninamine + putrescine = 5'-methylthioadenosine + spermidine."

FAG

Metabolic network: the mentioned reaction is the fifth (and the last) step in the biosynthesis of spermidine from arginine and methionine. The other steps are catalysed distinct enzymes - ornithine decarboxylase (GEM:02p25/ODC1), S-adenosylmethionine decarboxylase (GEM:06q2/AMD), and spermine synthase (EC:2.5.1.22; GEM:0Xp221/SMS; in human gene encoding this enzyme is not yet discovered.) In the catabolic pathway of polyamine metabolism, the N(1)-acetylation of spermidine and spermine is catalysed by spermidine/spermine N(1)-acetyltransferase (SPD/SPM acetyltransferase). The corresponding structural gene has been mapped: GEM:0Xp221/SAT."

PRT

"[1] Sequence: 302 aa; 33,824 Da.
------------------------------------------------------------------
From: Wahlfors J &: DNA Cell Biol, 9, 103-110, 1990;
Myohanen S &: DNA Cell Biol. 10, 467-474, 1991;
/Note: for more details, see the option 'Gene'.
--------- ____ ____-------------------------------------
{MEPGPDSIREGWFRETCSLWPGQALSLQVEQL LHHRRSRYQD = 50
ILVFRSKTYG NVLVLDGVIQ CTERDEFSYQ EMIANLPLCS HPNPRKVLII =100
GGGDGGVLRE VVKHPSVESV VQCEIDEDVI QVSKKFLPGM AIGYSSSKLT =150
LHVGDGFEFM KQNQDAFDVI ITDSSDPMGP AESLFKESYY QLMKTALKED =200
GVLCCQGECQ WLHLDLIKEM RQFCQSLFPV VAYAYCTIPT YPSGQIGFML =250
CSKNPSTNFQ EPVQPLTQQQ VAQMQLKYYN SDVHRAAFVL PEFARKALND VS} =302
----------------------------------------------------------
Features: segment (7..15) contains two repeats (Gly-Pro-Ala-Ala/
/gpaa) at the positions (7..10) and (12..15).
------------------------------------------------------------------
[3] Cross-References (Protein DBs):
swp:P19623/SPEE_HUMAN/Feb-01-1991/Dec-01-1992;
{spermidine synthase (putrescine aminopropyltransferase), SPS1}.
pir:A32610."

GEN

[1] cDNA 1237 bp {human spermidine synthase, complete cDNA}. ------------------------------------------------------------------ From: Wahlfors J, Alhonen L, Kauppinen L, Hyvonen T, Janne J, Eloranta TO; Human spermidine synthase: cloning and primary structure. DNA Cell Biol, 9, N2, 103-110, 1990; also see published erratum in: DNA Cell Biol, 9, N7, 543, 1990; Department of Biochemistry, University of Kuopio, Finland. ------------------------------------------------------------------ Features: 5'-NTL segment(=82): {1..82}; CDS(=906): {83..989}; 3'-NTL segment(=248): {990..1237}. ------------------------------------------------------------------
[2] gDNA 7623 bp {gnb:M64231/HUMSPERSYN/24-Jul-1991; human spermidine synthase gene, complete cds}. From: Myohanen S, Kauppinen L, Wahlfors J, Alhonen L, Janne J; Human spermidine synthase gene: structure and chromosomal localization; DNA Cell Biol, 10, N6 (Jul-Aug), 467-474, 1991. Department of Biochemistry & Biotechnology, University of Kuopio, Finland. ------------------------------------------------------------------ Features: \contig =1(M64231); 5'-NTC =1; UPE_i =2; prom-maj =1; cap =1; mRNA =1; 5'-NTL =1; exon_i =8; start =1; CDS =1; cds_i =8; stop =1; 3'-NTL =1; intron_i,j =7; pA-USE =1; pA-site =1; pA-DSE =1; 3'-NTC =1\ Gene(=~6000): {contig(1209..7157)}; 5'-NTC(=1314): {contig(1..1314)}; UPE_1: {5'-NTC(tgg|1212=CCAAT=1216|gag)}; UPE_2: {5'-NTC(ttg|1240=CCATT=1244|ggc)} /Note: the gnb:M64231's description of the given feature is as follows: ''CAAT_signal 1242..1246 /note='box 2''; prom-maj?: {5'-NTC(tcc|1261=GCCCC_CGCC_gg_cag_GCCCC_ GCCCCgCGCCcggg=1293|tta)} /Note: TATA-box is not identified within the segment (between UPE_2 and cap-site); cap-site: {contig(ggc|1315=G|ggc)}; mRNA(=1649): {exon_1:contig(1315..1563), > cds_1(=167(1397..1563)) exon_2:contig(1995..2115), = cds_2(=121) exon_3:contig(2448..2540), = cds_3(=93) exon_4:contig(4584..4737), = cds_4(=154) exon_5:contig(5247..5330), = cds_5(=84) exon_6:contig(5415..5560), = cds_6(=146) exon_7:contig(6255..6377), = cds_7(=123) exon_8:contig(6454..7132), > cds_8(=18(6454..6471))}; 5'-NTL(=82): {contig(1315..1396)}; CDS(=906): {start(1397=ATG)_cds_1,cds_2,cds_3,cds_4, cds_5,cds_6,cds_7,cds_8,stop(6472=TGA)}; 3'-NTL(=661): {contig(6472..7132)}; intron_1,2: {contig(1564..1994) = 431}; intron_2,3: {contig(2116..2447) = 332}; intron_3,4: {contig(2541..4583) =2043}; intron_4,5: {contig(4738..5246) = 509}; intron_5,6: {contig(5331..5414) = 84}; intron_6,7: {contig(5561..6254) = 694}; intron_7,8: {contig(6378..6453) = 76}; pA-USE?: {contig(cag|7071=AAAAATT=7077|ggg)}; pA-site: {contig(ggc|7126=AAATAcA=7132|gga)}; pA-DSE?: {contig(7136=aggggtggcggggctggtt=7154|acc)}; 3'-NTC(=491): {contig(7133..7623)}; -------------------------------------------------------------------
[3] Cross-references (DNA DBs): emb:M64231/HSSPERSYN/Oct-24-1991/Dec-20-1991; {human spermidine synthase gene, complete cds}.
[4] The following is a citation from Myohanen-1991:'Sequence analyses revealed that the gene comprised of 5,818 nucleotides from the cap site to the last A of the putative polyadenylation signal with 8 exons and 7 intervening sequences. The 5'-flanking region of the gene was extremely GC rich, lacking any TATA box but containing CCAAT consensus sequences. No perfect consensus sequence for the cAMP-responsive element for the AP-1 binding site was found, yet the gene contained seven AP-2 binding site consensus sequences. The putative polyadenylation signal was an unusual AATACA instead of AATAAA.' According to a HUGEN expert, the mentioned gene length (5,818 bp) was underestimated since it did not include 5'- and 3'-flanking regions containing several functionally important elements.
[5] The following is a citations from Wahlfors-1990: 'Starting from the first start codon, which was immediately preceded by a GC-rich region including four overlapping CCGCC consensus sequences, an open reading frame for a 302-amino-acid polypeptide was resolved. This peptide had an Mr of 33,827, started with methionine, and ended with serine. The coding strand of the cDNA revealed no special regulatory or ribosome-binding signals within 82 nucleotides preceding the start codon and no polyadenylation signal within 247 nucleotides following the stop codon. ..By computer analysis, the first 200 nucleotides of of the 5' end of the coding strand appear able to form a very stable secondary structure with a free energy change of -157.6 kcal/mole. The coding region, containing a 13-nucleotide repeat close to the 5'-end, was longer than, and very different from, that of the bacterial counterpart. This region seems to be of retroviral origin and shows marked homology with sequences found in a variety of human, mammalian, avian, and viral genes and mRNAs.'"

LIK

GEM:03^/SRML2.

REF

PEP,FUN "Hannonen P &: BBA, 289, 225-231, 1972
CLO,GEN,SEQ,LOC,MOL "Myohanen S &: DNA Cell Biol, 10, N6, 467-474, 1991
PEP,FUN "Pegg AE &: Biochem J, 197, 315-320, 1981
IDN,PEP,FUN "Tabor CW: Methods Enzymol, 5, 761-?, 1962
CLO,COD,PEP,SEQ,EXP "Wahlfors JJ &: DNA Cell Biol, 9, N2, 103-110, 1990a
CLO,COD,PEP,SEQ,EXP "Wahlfors JJ &: DNA Cell Biol, 9, (publ.err.), N7, 543, 1990b
LOC,CYG,MOL "Winqvist R &: CCG, 58, (HGM11), N1-4, 1865, 1991

SWI

 SWISSPROT: P19623

KEY

aac

CLA

coding, basic

LOC

01 p36-22

MIM

 MIM: 182891

EZN

 ENZYME: 2.5.1.16