Abstract
Dry lettuce seeds (achenes of Lactuca sativa L. cv. Grand Rapids) contain no detectable phenylalanine ammonia‐lyase (PAL, EC 4.3.1.5) activity. Enzyme activity could be detected in these seeds within 4 h of imbibition under white light. The specific activity of PAL increased rapidly during the next 12–16 h of imbibition. Far‐red light completely suppressed germination as well as the development of PAL. Gibberellic acid (GA 3 , 0.1 m M ), although effective in causing almost 100% germination in dark, did not induce proportionate increases in PAL. Seed germination as well as PAL activity were substantially inhibited by cis ‐4‐cyclohexene‐l, 2‐dicarboximide (CHDC, 1.0 m M ) both in light and dark. Both GA 3 and benzyladenine (BA, 0.1 m M ) retarded radicle elongation in light. Concomitantly, a decrease in PAL activity was observed. Benzyladenine was able to reverse the effects of CHDC on germination but PAL activity was still highly reduced, probably due to the inhibitory effects of BA on elongation of the radicle. More than 95% of the extractable PAL was found to be present in the radicle. When seeds incubated in white light for 10 h were transferred to FR, further increases in PAL activity as well as the growth of the radicle were severely inhibited. It is suggested that the induction of PAL in light‐sensitive lettuce seeds is coincidental with the germination of seeds, and the amount of PAL per germinated seed is related to the extent of elongation of the embryonic axes.
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Claims 19
Claim · model-written summary
Dry lettuce seeds had no detectable PAL activity.
- Taxon
- Lactuca sativa
Lactuca sativae0 - Material
- Grand Rapidse0
- Gene
- phenylalanine ammonia‐lyasee0
- Outcome
- no detectable phenylalanine ammonia‐lyase (PAL, EC 4.3.1.5) activitye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Dry lettuce seeds (achenes of Lactuca sativa L. cv. Grand Rapids) contain no detectable phenylalanine ammonia‐lyase (PAL, EC 4.3.1.5) activity.”
Claim · model-written summary
PAL became detectable within 4 hours of imbibition under white light.
- Taxon
- Lactuca sativaLactuca sativat0
- Organ / stage
- seedse0
- Treatment
- white lighte0
- Outcome
- Enzyme activitye0
- Value
- 4 he0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Enzyme activity could be detected in these seeds within 4 h of imbibition under white light.”
t0“Lactuca sativa”
Claim · model-written summary
PAL specific activity increased rapidly over the next 12–16 hours.
- Taxon
- Lactuca sativaLactuca sativat0
- Gene
- PALe0
- Outcome
- specific activity of PALe0
- Direction
- increasede0
- Value
- 12–16 he0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The specific activity of PAL increased rapidly during the next 12–16 h of imbibition.”
t0“Lactuca sativa”
Claim · model-written summary
Far-red light suppressed germination.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Far‐red lighte0
- Outcome
- germinatione0
- Direction
- suppressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Far‐red light completely suppressed germination as well as the development of PAL.”
t0“Lactuca sativa”
Claim · model-written summary
Far-red light suppressed PAL development.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Far‐red lighte0
- Gene
- PALe0
- Outcome
- development of PALe0
- Direction
- suppressede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Far‐red light completely suppressed germination as well as the development of PAL.”
t0“Lactuca sativa”
Claim · model-written summary
GA3 caused almost complete dark germination without proportionate PAL increase.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Gibberellic acid (GA 3 , 0.1 m M )e0
- Outcome
- germination in darke0
- Direction
- effectivee0
- Value
- almost 100%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Gibberellic acid (GA 3 , 0.1 m M ), although effective in causing almost 100% germination in dark, did not induce proportionate increases in PAL.”
t0“Lactuca sativa”
Claim · model-written summary
GA3 did not induce proportionate increases in PAL.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Gibberellic acid (GA 3 , 0.1 m M )e0
- Outcome
- PALe0
- Direction
- did not induce proportionate increasese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Gibberellic acid (GA 3 , 0.1 m M ), although effective in causing almost 100% germination in dark, did not induce proportionate increases in PAL.”
t0“Lactuca sativa”
Claim · model-written summary
CHDC inhibited germination in light and dark.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- cis ‐4‐cyclohexene‐l, 2‐dicarboximide (CHDC, 1.0 m M )e0
- Outcome
- Seed germinatione0
- Direction
- inhibitede0
- Qualifier
- both in light and darke0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Seed germination as well as PAL activity were substantially inhibited by cis ‐4‐cyclohexene‐l, 2‐dicarboximide (CHDC, 1.0 m M ) both in light and dark.”
t0“Lactuca sativa”
Claim · model-written summary
CHDC inhibited PAL activity in light and dark.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- cis ‐4‐cyclohexene‐l, 2‐dicarboximide (CHDC, 1.0 m M )e0
- Outcome
- PAL activitye0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Seed germination as well as PAL activity were substantially inhibited by cis ‐4‐cyclohexene‐l, 2‐dicarboximide (CHDC, 1.0 m M ) both in light and dark.”
t0“Lactuca sativa”
Claim · model-written summary
GA3 retarded radicle elongation in light.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- GA 3e0
- Outcome
- radicle elongatione0
- Direction
- retardede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Both GA 3 and benzyladenine (BA, 0.1 m M ) retarded radicle elongation in light.”
t0“Lactuca sativa”
Claim · model-written summary
Benzyladenine retarded radicle elongation in light.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- benzyladenine (BA, 0.1 m M )e0
- Outcome
- radicle elongatione0
- Direction
- retardede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Both GA 3 and benzyladenine (BA, 0.1 m M ) retarded radicle elongation in light.”
t0“Lactuca sativa”
Claim · model-written summary
PAL activity declined concurrently.
- Taxon
- Lactuca sativaLactuca sativat0
- Outcome
- PAL activitye0
- Direction
- decreasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Concomitantly, a decrease in PAL activity was observed.”
t0“Lactuca sativa”
Claim · model-written summary
Benzyladenine reversed CHDC effects on germination.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Benzyladeninee0
- Outcome
- germinatione0
- Direction
- reversee0
- Comparator
- CHDCe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Benzyladenine was able to reverse the effects of CHDC on germination but PAL activity was still highly reduced, probably due to the inhibitory effects of BA on elongation of the radicle.”
t0“Lactuca sativa”
Claim · model-written summary
PAL activity remained highly reduced with benzyladenine after CHDC.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- Benzyladeninee0
- Outcome
- PAL activitye0
- Direction
- reducede0
- Comparator
- CHDCe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Benzyladenine was able to reverse the effects of CHDC on germination but PAL activity was still highly reduced, probably due to the inhibitory effects of BA on elongation of the radicle.”
t0“Lactuca sativa”
Claim · model-written summary
More than 95% of extractable PAL was in the radicle.
- Taxon
- Lactuca sativaLactuca sativat0
- Organ / stage
- radiclee0
- Outcome
- extractable PALe0
- Value
- More than 95%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“More than 95% of the extractable PAL was found to be present in the radicle.”
t0“Lactuca sativa”
Claim · model-written summary
Transfer from white light to far red severely inhibited subsequent PAL increase.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- transferred to FRe0
- Outcome
- further increases in PAL activitye0
- Direction
- inhibitede0
- Comparator
- white lighte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When seeds incubated in white light for 10 h were transferred to FR, further increases in PAL activity as well as the growth of the radicle were severely inhibited.”
t0“Lactuca sativa”
Claim · model-written summary
Transfer from white light to far red severely inhibited radicle growth.
- Taxon
- Lactuca sativaLactuca sativat0
- Treatment
- transferred to FRe0
- Outcome
- growth of the radiclee0
- Direction
- inhibitede0
- Comparator
- white lighte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When seeds incubated in white light for 10 h were transferred to FR, further increases in PAL activity as well as the growth of the radicle were severely inhibited.”
t0“Lactuca sativa”
Claim · model-written summary
PAL induction was suggested to coincide with seed germination.
- Taxon
- lettuceLactuca sativae0
- Organ / stage
- seedse0
- Outcome
- induction of PALe0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It is suggested that the induction of PAL in light‐sensitive lettuce seeds is coincidental with the germination of seeds, and the amount of PAL per germinated seed is related to the extent of elongation of the embryonic axes.”
Claim · model-written summary
PAL amount per germinated seed was related to embryonic axis elongation.
- Taxon
- lettuceLactuca sativae0
- Organ / stage
- embryonic axese0
- Outcome
- amount of PAL per germinated seede0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It is suggested that the induction of PAL in light‐sensitive lettuce seeds is coincidental with the germination of seeds, and the amount of PAL per germinated seed is related to the extent of elongation of the embryonic axes.”
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