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R H Kloth

Publications and source records attributed to R H Kloth.

3 recordsLinked to original sources

Identification of a delta-TIP cDNA clone and determination of related A and D genome subfamilies in Gossypium species.

Tonoplast intrinsic proteins (TIPs) have been implicated in the process of cell elongation, such as occurs in the developing cotton fiber. We have isolated a cDNA clone (997 bp in length) from a cotton (Gossypium hirsutum L.) library which putatively encodes a protein of 248 residues (Mr 25079) with 85% identity to Arabidopsis delta-TIP. The derived amino acid sequence included two conserved sequences associated with major intrinsic proteins (SGxHxNPA at residues 78 to 85, NPA residues at 197 to 199) and a cysteine residue at 116 which is reported to bind mercury in Arabidopsis delta-TIP. The polymerase chain reaction was used to generate partial genomic clones of the cotton delta-TIP. In comparison to other genomic TIP sequences, the number (two) and position of the introns were conserved in cotton. Comparing the TIP sequences from cotton revealed two subfamilies, which were consistently distinguished by a Tsp45I restriction site polymorphism. This polymorphism was used to demonstrate that TIP subfamilies were specific to either the A or D genomes of Gossypium. When delta-TIP DNA fragments were amplified from cDNA of fiber 14 days after anthesis, the A and D were found, indicating the presence of delta-TIP transcripts in these elongating cells.

Amino Acid Sequence↗

Identification of a third fuzzless seed locus in upland cotton (Gossypium hirsutum L.).

Segregating populations were developed to evaluate the inheritance of the fuzzless seed phenotypes in upland cotton (Gossypium hirsutum L.). Accession 143 of the Mississippi Obsolete Variety Collection (MOVC) has a fuzzless seed phenotype. This line carries the n(2) locus which is recessive to the seed fuzz phenotype. Data from the F(2), BC(1)F(1), F(2:3), and BC(1)F(2) populations of DP 5690 x 143 fit a two-loci model for expression of the recessive fuzzless seed phenotype. Fuzzless seeds were obtained in n(2)n(2) plants when a second recessive locus (n(3)) was present. The dominant N(3) allele found in DP 5690 confers the fuzzy seed phenotype in homozygous n(2) plants. Accession 243 of the MOVC carries the N(1) locus, which is dominant to the presence of seed coat fuzz. No variation from expected ratios was observed in the F(2), BC(1)F(1), F(2:3), and BC(1)F(2) populations of the DP 5690 x 243 cross. The N(3) allele had no apparent effect on the expression of the N(1) locus. In a cross between accessions 243 x 143, a few plants were observed which were completely devoid of lint and fuzz fiber (fiberless). A fiberless line was developed from one of these fiberless plants. This line was designated MD 17 fiberless. In a cross between DP 5690 x MD 17 fiberless, we demonstrated that at least three loci were involved in the expression of the fiberless phenotype. The involvement of n(2) and n(3) in the expression of this fiberless phenotype was demonstrated in the F(2) progeny of the cross between 143 x MD 17 fiberless. This is the first demonstration that N(1), n(2), and n(3) interacted to produce fiberless seed.

Crosses, Genetic↗