Chlorophyll a/b binding (CAB) polypeptides of CP29, the internal chlorophyll a/b complex of PSII: characterization of the tomato gene encoding the 26 kDa (type 1) polypeptide, and evidence for a second CP29 polypeptide

CP29, the core chlorophyll a/b (CAB) antenna complex of Photosystem II (PSII), has two nuclearencoded polypeptides of approximately 26 and 28 kDa in tomato ( Lycopersicon esculentum ). Cab9, the gene for the Type 1 (26 kDa) CP29 polypeptide was cloned by immunoscreening a tomato leaf cDNA library. Its identity was confirmed by sequencing tryptic peptides from the mature protein. Cab9 is a single-copy gene with five introns, the highest number found in a CAB protein. In vitro transcription-translation gave a 31 kDa precursor which was cleaved to about 26 kDa after import into isolated tomato chloroplasts. The Cab9 polypeptide has the two highly conserved regions common to all CAB polypeptides, which define the members of this extended gene family. Outside of the conserved regions, it is only slightly more closely related to other PSII CABs than to PSI CABs. Sequence analysis of tryptic peptides from the Type II (28 kDa) CP29 polypeptide showed that it is also a member of the CAB family and is very similar or identical to the CP29 polypeptide previously isolated from spinach. All members of the CAB family have absolutely conserved His, Gln and Asn residues which could ligate the Mg atoms of the chlorophylls, and a number of conserved Asp, Glu, Lys and Arg residues which could form H-bonds to the polar groups on the porphyrin rings. The two conserved regions comprise the first and third predicted trans-membrane helices and the stroma-exposed segments preceding them.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47577/1/438_2004_Article_BF00259681.pd

Mortality differences by partnership status in England and Wales : the effect of living arrangements or health selection?

Sebastian Franke’s research was supported by the Economic and Social Research Council [ES/J500094/1] through the North West Doctoral Training Centre Social Statistics pathway (Ph.D. project: “Health, Mortality and Partnership Status: Protection or Selection”). The permission of the Office for National Statistics to use the Longitudinal Study is gratefully acknowledged, as is the help provided by staff of the Centre for Longitudinal Study Information and User Support (CeLSIUS). CeLSIUS is supported by the ESRC Census of Population Programme (Award Ref: ES/K000365/1).This paper investigates the relationship between partnership status and mortality in England and Wales. Using data from the Office for National Statistics Longitudinal Study (ONS LS) for the period between 2001 and 2011, we examine whether married people have lower mortality levels than unmarried individuals; whether individuals who cohabit have mortality levels similar to those of married or single persons; and how much the fact that married couples live with someone rather than alone explains their low mortality. Our analysis shows first that married individuals have lower mortality than unmarried persons. Second, men and women in pre-marital unions exhibit mortality levels similar to those of married men and women, whereas mortality levels are elevated for post-marital cohabitants. Third, controlling for household size and the presence of children reduces mortality differences between married and unmarried non-partnered individuals, but significant differences persist. The study supports both protection and selection theory. The increase in mortality differences by age group between never-married cohabitants and married couples is likely a sign of the long-term accumulation of health and wealth benefits of marriage. Similar mortality levels of cohabiting and married couples at younger ages suggest that healthier individuals are more likely to find a partner.PostprintPeer reviewe

Sorting of proteins to vacuoles in plant cells

for correspondence