Identification of enhanced protein bands in quality protein maize (QPM) lines /
The main goal of this study was to identify specific non-zein proteins associated with lysine enhanced expression within and among triads during QPM conversion. Maize endosperm proteins in the [ ] and QPM seeds showed a shift from zein to non-zeins at maturity. Among non-zeins, glutelin proteins w...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742535011&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The main goal of this study was to identify specific non-zein proteins associated with lysine enhanced expression within and among triads during QPM conversion. Maize endosperm proteins in the [ ] and QPM seeds showed a shift from zein to non-zeins at maturity. Among non-zeins, glutelin proteins were the targets to increase lysine content in QPM due to their higher percentage of composition (29-48%)4than the albumin and globulin fractions (3-8%). QPM endospen-n had higher amounts of glutelin than D2 or normal endospen-n in the triads, and glutelin content was significantly correlated to lysine level. In addition, kernel density data indicate that QPM had higher density than 22 maize. Seventeen glutelin bands were visible following gel electrophoresis during seed development. The expressions of 26, 48 and 90 kd glutelin bands at 45 DAP were consistently enhanced in most QPM lines compared to 92 inbreds. These elevated glutelins conferred high kernel density in the QPMS. In addition, lysine content of 90, 48 and 26 kd glutelin bands of QPM lines was consistently increased relative to normal lines. The higher lysine content in QPM, relative to normal corn was related to the three lysine-enriched glutetin bands. These three lysine-enriched, glutelin-enhanced bands may affect the kernel density and quality improvement in selected QPM lines. Protein accumulation in the different lines varied with maturity, but, as endosperm maturation proceeded, the accumulation of each protein fraction increased. The accumulation rate of each fraction was higher between 15 to 25 DAP than at other stages of seed development. In all o2 and QPM fines, zein accumulation was delayed and reduced compared to normal seed. Zein profiles illustrate that the 23 kd band (a-zein) was suppressed in all o2 and QPM lines analyzed. This implies that homozygous o2/o2 was maintained in the QPM inbreds during selection. |
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| Item Description: | Vita. "Major Subject: Plant Breeding". |
| Physical Description: | xiii, 95 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |